Tech4Biowaste - User contributions [en]

Hydrolysis

2021-12-17T11:36:32Z

Margaux Lambrecht: /* Patents */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemicellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkali ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Cellulase enzymes ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

......

==== Hemicellulase enzymes ====
........

==== Ligninolytic enzymes ====
.... (See reference 11)

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.

11. Enzymatic hydrolysis of lignin by ligninolytic enzymes and analysis of the hydrolyzed lignin products Sitong Zhang, Jianlong Xiao, Gang Wang, Guang Chen
[[Category:Primary processing]]

Hydrolysis

2021-12-17T11:35:51Z

Margaux Lambrecht: /* Hemi-cellulose */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemicellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkali ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Cellulase enzymes ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

......

==== Hemicellulase enzymes ====
........

==== Ligninolytic enzymes ====
.... (See reference 11)

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''

11. Enzymatic hydrolysis of lignin by ligninolytic enzymes and analysis of the hydrolyzed lignin products Sitong Zhang, Jianlong Xiao, Gang Wang, Guang Chen
[[Category:Primary processing]]

Hydrolysis

2021-12-17T11:33:28Z

Margaux Lambrecht: /* Acid hydrolysis */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkali ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Cellulase enzymes ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

......

==== Hemicellulase enzymes ====
........

==== Ligninolytic enzymes ====
.... (See reference 11)

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''

11. Enzymatic hydrolysis of lignin by ligninolytic enzymes and analysis of the hydrolyzed lignin products Sitong Zhang, Jianlong Xiao, Gang Wang, Guang Chen
[[Category:Primary processing]]

Hydrolysis

2021-12-17T11:29:20Z

Margaux Lambrecht: /* References */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Cellulase enzymes ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

......

==== Hemicellulase enzymes ====
........

==== Ligninolytic enzymes ====
.... (See reference 11)

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''

11. Enzymatic hydrolysis of lignin by ligninolytic enzymes and analysis of the hydrolyzed lignin products Sitong Zhang, Jianlong Xiao, Gang Wang, Guang Chen
[[Category:Primary processing]]

Hydrolysis

2021-12-17T11:23:13Z

Margaux Lambrecht: /* Chemical hydrolysis */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:44:22Z

Margaux Lambrecht: /* Subcritical water */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH), also called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathe''rmolysis, has potential for breaking down the cellulose and hemicellulose biopolymers into simple sugars and small molecules. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:41:23Z

Margaux Lambrecht: /* Organosolv */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv (lignin hydrolysis) =====
Organosolv pretreatment is the process to extract lignin from lignocellulosic feedstocks with organic solvents or their aqueous solutions.

In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:36:58Z

Margaux Lambrecht: /* Feedstock */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Structural features ===

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv =====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:35:26Z

Margaux Lambrecht: /* Solvent */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

==== Solvent ====
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

===== Organosolv =====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

===== Ionic Liquids=====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

==== Subcritical water ====
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:34:29Z

Margaux Lambrecht: /* Enzymatic hydrolysis of lignin */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====
........

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:33:57Z

Margaux Lambrecht: /* Enzymatic hydrolysis */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

==== Enzymatic hydrolysis of cellulose ====
The hydrolysis of cellulose in native lignocellulosic material is slow and is primarily governed by structural features of the lignocellulosic biomass:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

........

==== Enzymatic hydrolysis of hemi-cellulose ====
........

==== Enzymatic hydrolysis of lignin ====

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:24:47Z

Margaux Lambrecht: /* Ionic Liquids */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:21:14Z

Margaux Lambrecht: /* Hydrochloric acid */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

=== Biological hydrolysis ===
Lignin degradation can also occur through the action of lignin degrading enzymes secreted by microorganisms (e.g. fungi).

== Product==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:10:49Z

Margaux Lambrecht: /* Hydrochloric acid */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Hydrochloric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

== Product ==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T10:09:58Z

Margaux Lambrecht: /* Chemical processing */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical hydrolysis ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid hydrolysis ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

Acid hydrolysis can be further improved by the addition of salts, such as metal salts or suphite salts. Metals such as aluminium, calcium, copper, iron and zincnc can be used to increase the sugar yield [6]. Similar to sulphite pulping, sulphites can be added to aid in lignin removal. .

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Hydrochloric acid''' =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkaline hydrolysis ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

== Product ==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T09:46:05Z

Margaux Lambrecht: /* Pre-treatment */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
''Explain structure of cellulose''

==== Hemi-cellulose ====
''Explain structure of hemi-cellulose''

==== Lignin ====
''Explain structure of Lignin''

== Process and technologies ==

=== Chemical processing ===
Chemical pretreatments have been used extensively for removal of lignin surrounding cellulose and for destroying its crystalline structure. Even though chemical pretreatments are usually effective, they have disadvantages which should not be ignored [10]. These include use of specialized corrosion resistant equipment, need for extensive washing, and disposal of chemical wastes. Various chemical methods are discussed under several headings, namely, alkalis, acids, gases, oxidizing agents, cellulose solvents, extraction, and swelling agents.

==== Acid ====
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. Acids are used mainly for hydrolysis of cellulose [10]. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>

===== Sulfuric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Hydrochloric acid''' =====
''Elaborate more the reactions conditions and give some examples from literature.''

===== Phosphoric acid =====
''Elaborate more the reactions conditions and give some examples from literature.''

==== Alkali ====
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

===== Sodium hydroxide =====
Dilute sodium hydroxide (NaOH) treatment of lignocellulosic material causes swelling, leading to an increase in internal surface area, decrease in the degree of polymerization, decrease in crystallinity, separation of structural linkages between lignin and carbohydrates, and disruption of the lignin structure [10].

''Elaborate more the reactions conditions and give some examples from literature.''

===== '''Ammonia''' =====
Liquid or gaseous ammonia acts as a strong swelling agent for cellulose [1].

''Elaborate more the reactions conditions and give some examples from literature.''

===== Ammonium sulfite =====
Ammonium sulfite is used mainly in a conventional pulping process.

''Elaborate more the reactions conditions and give some examples from literature.''

=== Salt ===
Hydrolysis can be further improved by the addition of salts, such as metal salts or sulphite salts.

==== Metals salts ====
Acid hydrolysis can be stimulated by the addition of '''metal chlorides'''. Metals such as aluminium, calcium, copper, iron, and zinc can be used to increase the sugar yield.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Sulphite salt ====
Similar to [[Pulping#Sulphite pulping|sulphite pulping]], sulphites can be added to acid hydrolysis to aid in lignin removal.

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0" />

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

== Product ==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Pre-processing

2021-12-17T09:14:10Z

Margaux Lambrecht: /* Chemical processes and technologies */

<onlyinclude>'''Pre-processing''' technologies are utilised in the pre-treatment of biowaste to obtain chemicals and/or materials which will then go into the [[conversion]] followed by an optional [[post-processing]] after which the final product is obtained. While some technologies are used exclusively for the purpose of pre-processing, others such as the separation processes and technologies can be utilised in both pre- and [[post-processing]].</onlyinclude>

== Chemical processes and technologies==

* [[Hydrolysis]]
** [[Hydrolysis#Acid|Acid]]
** [[Hydrolysis#Alkali|Alkali]]
** [[Hydrolysis#Salt|Salt]]
*** [[Hydrolysis#Metal%20salts|Metal salts]]
*** [[Hydrolysis#Sulphite%20salt|Sulphite salt]]
** [[Hydrolysis#Solvent|Solvent]]
*** [[Hydrolysis#Organosolv|Organosolv]]
* [[Ionic liquids]]
* [[Oxidation]]

== Physical processes and technologies ==

* [[Densification]]
* [[Sizing]]
** [[Sizing#Chipping|Chipping]]
** [[Sizing#Grinding|Grinding]]
* [[Microwave treatment]]
* [[Steam explosion]]
* [[Ultrasonication]]

== Separation technologies ==

* Mechanical separations
** [[Centrifugation]]
** [[Membrane filtration]]
** [[Particle classification, sieving]]
** [[Particle filtering]]
* Physicochemical separations
** [[Chromatography]]
** [[Crystallisation and precipitation]]
** [[Distillation]]
** [[Drying]]
*** [[Drying#Air%20drying|Air drying]]
*** [[Drying#Nitrogen%20drying|Nitrogen drying]]
*** [[Drying#Freeze%20drying|Freeze drying]]
*** [[Drying#Thermal%20drying|Thermal drying]]
*** [[Drying#Vacuum%20drying|Vacuum drying]]
** [[Extraction]]
** [[Field-Flow fractionation (FFF)]]
*** [[Field-Flow fractionation (FFF)#Asymmetric%20flow%20FFF%20.28AF4.29|Asymmetric flow FFF (AF4)]]
*** [[Field-Flow fractionation (FFF)#Centrifugal%20FFF|Centrifugal FFF]]
*** [[Field-Flow fractionation (FFF)#Electrical%20FFF|Electrical FFF]]
*** [[Field-Flow fractionation (FFF)#Split%20flow%20thin-cell%20fractionation%20.28SPLITT.29|Split flow thin-cell fractionation (SPLITT)]]
*** [[Field-Flow fractionation (FFF)#Thermal%20FFF|Thermal FFF]]
** [[Flocculation]]

== Thermochemical processes and technologies ==

* [[Ammonia fibre expansion]]

[[Category:Primary processing|!]]

Hydrolysis

2021-12-17T09:12:24Z

Margaux Lambrecht: /* Feedstock */

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

==== Cellulose ====
Explain structure of cellulose

==== Hemi-cellulose ====
Explain structure of hemi-cellulose

==== Lignin ====
Explain structure of Lignin

=== Pre-treatment ===

* [[Sizing]]
*....

== Process and technologies ==

=== Acid ===
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>
=== Alkali ===
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

=== Salt ===
Hydrolysis can be further improved by the addition of salts, such as metal salts or sulphite salts.

==== Metals salts ====
Acid hydrolysis can be stimulated by the addition of '''metal chlorides'''. Metals such as aluminium, calcium, copper, iron, and zinc can be used to increase the sugar yield.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Sulphite salt ====
Similar to [[Pulping#Sulphite pulping|sulphite pulping]], sulphites can be added to acid hydrolysis to aid in lignin removal.

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0" />

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

== Product ==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Hydrolysis

2021-12-17T08:49:33Z

Margaux Lambrecht:

{{Infobox technology|Name=Hydrolysis|Category=Pre-processing|Feedstock=Lignocellulosic biomass|Product=Sugars and organic acids}}
<onlyinclude>'''Hydrolysis''' (/haɪˈdrɒlɪsɪs/; from Ancient Greek ''hydro-'' 'water', and ''lysis'' 'to unbind') is a chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions that use water as the reagent.<ref>{{Cite web|year=2002|title=Hydrolysis|e-pub date=2002|date accessed=2021|url=https://en.wikipedia.org/wiki/Hydrolysis|Author=Wikipedia}}</ref> In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars. Hemicellulose is easier to hydrolyse than cellulose.<ref>{{Cite journal|title=Dilute acid hydrolysis of lignocellulosic biomass|year=2010-01-15|author=P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker|journal=Chemical Engineering Journal|volume=156|issue=2|page=395–403|doi=10.1016/j.cej.2009.10.061}}</ref> The result of hydrolysing hemicellulose and cellulose are sugars (glucose, mannose, galactose, (C6) and xylose, arabinose (C5)) and organic acids (formic acid and acetic acid).<ref>{{Cite journal|title=Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation|year=2020-04-17|author=Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach|journal=Catalysts|volume=10|issue=4|page=437|doi=10.3390/catal10040437}}</ref> </onlyinclude>

== Feedstock ==

=== Origin and composition ===
Hydrolysis can be performed as a pretreatment on any biowaste with a high lignocellulose content. Lignocellulose is typically the nonedible part of a plant, composed of a complex of cellulose, hemi-cellulose and lignin. Suitable feedstocks include grasses, straw, leaves, stems, shells, manure, paper waste, and others. The ratio between cellulose, hemi-cellulose and lignin varies wildly depending on the specific feedstock.<ref name=":1" />

=== Pre-treatment ===

* [[Sizing]]
*

== Process and technologies ==

=== Acid ===
'''Acid hydrolysis''' is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. A strong acid, such as formic, hydrochloric, nitric, phosphoric, or sulphuric acid can be used in concentrated or diluted form. '''Concentrated acid''' (10-30 %) can penetrate the lignin structure and break down the cellulose and hemicellulose to individual sugars at low temperature and with high yield. Downsides are the high acid consumption and high corrosion potential. These downsides are circumvented with the use of '''diluted acid''' (2-5 %). However, in the latter case, higher temperature is required, which can lead to side product formation such as furfural and 5-hydroxymethyl-furfural.<ref name=":1">{{Cite book|author=Alessandra Verardi, Isabella De Bari, Emanuele Ricca and Vincenza Calabrò|year=2012|section_title=Hydrolysis of Lignocellulosic Biomass: Current Status of Processes and Technologies and Future Perspectives|editor=Marco Aurelio Pinheiro Lima and Alexandra Pardo Policastro Natalense|book_title=Bioethanol|publisher=IntechOpen}}</ref>
=== Alkali ===
'''Alkaline hydrolysis''' refers to hydrolysis reactions using hydroxide, commonly from sodium hydroxide or calcium hydroxide. The hydroxide breaks down the lignin bonds to make the cellulose more accessible. The reaction proceeds at lower temperature and pressure and residual alkali can be recycled. However, the pretreatment does result in irrecoverable salts in the product.<ref>{{Cite journal|title=Pretreatment of lignocellulosic sugarcane leaves and tops for bioethanol production|year=2020-01-01|journal=Lignocellulosic Biomass to Liquid Biofuels|page=301–324|doi=10.1016/B978-0-12-815936-1.00010-1|author=S. Niju, M. Swathika, M. Balajii|volume=}}</ref>

=== Salt ===
Hydrolysis can be further improved by the addition of salts, such as metal salts or sulphite salts.

==== Metals salts ====
Acid hydrolysis can be stimulated by the addition of '''metal chlorides'''. Metals such as aluminium, calcium, copper, iron, and zinc can be used to increase the sugar yield.<ref name=":0">{{Cite journal|title=A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities|year=2016-01-01|journal=Bioresource Technology|volume=199|page=92–102|doi=10.1016/j.biortech.2015.07.106|author=Amit K. Jaiswal, Rajeev Ravindran}}</ref>

==== Sulphite salt ====
Similar to [[Pulping#Sulphite pulping|sulphite pulping]], sulphites can be added to acid hydrolysis to aid in lignin removal.

=== Solvent ===
Solvents can be added to improve the hydrolysis process. This is similar to [[Pulping#Dissolving pulp and organosolv|organosolv pulping]], but without the delignification as goal.<ref name=":2">{{Cite journal|title=Biomass pretreatment: Fundamentals toward application|year=2011-11|author=Valery B. Agbor, Nazim Cicek, Richard Sparling, Alex Berlin, David B. Levin|journal=Biotechnology Advances|volume=29|issue=6|page=675–685|doi=10.1016/j.biotechadv.2011.05.005}}</ref>

==== Organosolv ====
In an '''organosolv hydrolysis''' organic solvents are added to the process, usually performed at high temperatures (100-250 °C). This can be combined with a catalyst such as HCl or H2SO4.<ref name=":2" /> For example, in '''acid-acetone''' pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone.<ref name=":0" />

==== Ionic Liquids ====
Ionic liquids are '''solvents''' that can be used for biomass pretreatment, fractionation, and dissolution. During ionic liquid pretreatment, a cellulose-rich fraction can be generated through the degradation and removal of a large portion of lignin and hemicellulose <ref>{{Cite web|Author=Moyer, P., Kim, K., Abdoulmoumine, N. et al.|year=2018|title=Structural changes in lignocellulosic biomass during activation with ionic liquids comprising 3-methylimidazolium cations and carboxylate anions|e-pub date=27/09/2018|date accessed=06/12/2021|url=https://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/s13068-018-1263-0}}</ref>

=== Subcritical water ===
Subcritical water hydrolysis (SWH) can also be called h''ydrothermal liquefaction'', ''hydrothermolysis'', or ''aquathermolysis''. The technique uses water at high temperatures and pressures to keep it in a liquid form. SWH can reduce reaction time and thereby degradation product formation, generates less waste water and lower corrosion requirements.<ref>{{Cite journal|title=Subcritical water hydrolysis of sugarcane bagasse: An approach on solid residues characterization|year=2016-02-01|author=D. Lachos-Perez, F. Martinez-Jimenez, C. A. Rezende, G. Tompsett, M. Timko, T. Forster-Carneiro|journal=The Journal of Supercritical Fluids|volume=108|page=69–78|doi=10.1016/j.supflu.2015.10.019}}</ref>

=== Enzymatic hydrolysis ===
Enzymatic hydrolysis is a catalytic decomposition of a chemical compound by reaction with water, such as the conversion of lignocellulosic materials, by the addition of specific enzymes.

However, the hydrolysis of native lignocellulosic material is slow and is primarily governed by their structural features, since:

1. cellulose present in biomass possesses highly resistant crystalline structure;

2. lignin surrounding the cellulose forms a physical barrier;

3. The sites available for enzymatic attack are limited.

The cellulose present in lignocellulosic materials is composed of crystalline and amorphous components. The amorphous component is more susceptible to enzymatic attack than the crystalline component. The presence of lignin forms a physical barrier for enzymatic attack; therefore, treatments causing disruption of the lignin seal will increase the accessibility of cellulose to enzyme molecules and eventually its hydrolysis rate. The limitation of available sites for enzymatic attack stems from the fact that the average size of the capillaries in biomass is too small to allow the entry of large enzyme molecules; and thus, enzymatic attack is confined to the external surface [10].

Pretreatment, therefore, is an essential prerequisite to enhance the susceptibility of lignocellulosic materilas to enzyme action. An ideal pretreatment would accomplish reduction in lignin content, concommitant with a reduction in crystallinity, and an increase in surface area. The variety of pretreatments can be classified into physical, chemical, and biological depending on the mode of their action [10].

== Product ==
Hydrolysis is generally performed on cellulose and hemi-cellulose, which results in different sugars: glucose, mannose, and galactose as C6 sugars, and xylose and arabinose asC5 sugars. Next to these, organic acids are often formed in formic acid and acetic acid.

=== Post-treatment ===
Currently no post-treatment has been identified.

== Technology providers ==
{| class="wikitable sortable mw-collapsible mw-collapsed"
|+'''Technology comparison'''
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Company name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Country
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology category
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Technology name
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| TRL
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Capacity [kg/h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Catalyst loading [wt %]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| pH
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Pressure [bar]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Reactor
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Residence time [h]
! class="cd-text-darkgreen" style="vertical-align:{{{va|bottom}}}"| Temperature [°C]
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Food waste
! class="cd-text-darkgreen" style="{{writing-mode|s2}};vertical-align:{{{va|bottom}}}"| Feedstock: Garden & park waste
|-
! style="height:1.8em;"|
!
!
!
!
!
!
!
!
!
!
!
!
!
|-
| [[Help:Article content of technology pages#Company_1|Company 1]]
| [Country HQ location]
| [Technology category (if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|-
| [[Help:Article content of technology pages#Company_2|Company 2]]
| [Country HQ location]
| [(if different sub-categories are defined this has to be specified here, the available categories can be found on each technology page under the chapter [[Help:Article content of technology pages#Process_and_technologies|Process and technologies]])]
| [Technology name (the "branded name" or the usual naming from company side)]
| [4-9]
| [numeric value]
|
|
|
|
|
|
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
| class="cd-background-lightgreen cd-text-darkgreen" style="text-align:center" |●
|}

=== NextChem ===

=== Valmet Oyj ===
{{Infobox provider-hydrolysis|Company=Valmet Oyj|Webpage=https://www.valmet.com/|Country=Finland|Technology name=BioTrac|Technology category=Chemical processes and technologies|TRL=9|Capacity=biomass feed up to 800 tonne/day|Reactor=Horizontal tube reactor|Temperature=High|Catalyst=Acidic conditions|Feedstock=All lignocellulosic biomass, including wood and forestry residues, wheat straw, corn stover and bagasse}}

== Open access pilot and demo facility providers ==
[https://biopilots4u.eu/database?field_technology_area_data_target_id=107&field_technology_area_target_id%5B85%5D=85&field_contact_address_value_country_code=All&field_scale_value=All&combine=&combine_1= Pilots4U Database]

== Patents ==
Currently no patents have been identified.

== References ==
<references />10. ''The Nature of Lignocellulosics and Their Pretreatments for Enzymatic Hydrolysis L. T. Fan, Young-Hyun Lee and M. M. Gharpuray Department of Chemical Engineering Kansas State University Manhattan, KS 66506/U.S.A.''
[[Category:Primary processing]]

Chromatography

2021-11-29T15:41:47Z

Margaux Lambrecht: /* ABC */

<onlyinclude>'''Chromatography''' is a laboratory technique for the separation of a mixture and may be preparative or analytical. The purpose of preparative chromatography is to separate the components of a mixture for later use, and is thus a form of purification. Analytical chromatography is done normally with smaller amounts of material and is for establishing the presence or measuring the relative proportions of analytes in a mixture. The two are not mutually exclusive.</onlyinclude>

==Input==
x
==Process and technologies==
The mixture is dissolved in a fluid (gas or solvent) called the ''mobile phase,'' which carries it through a system (a column, a capillary tube, a plate, or a sheet) on which a material called the ''stationary phase'' is fixed''.'' The different constituents of the mixture have different affinities for the stationary phase. The different molecules stay longer or shorter on the stationary phase, depending on their interactions with its surface sites. So, they travel at different apparent velocities in the mobile fluid, causing them to separate. The separation is based on the differential partitioning between the mobile and the stationary phases. Subtle differences in a compound's partition coefficient result in differential retention on the stationary phase and thus affect the separation.
==Output==
x
==Technology providers==
===ABC===
describe the company, here is an example

''ABC was founded in 20... 12 by KNN and Syncom, in collaboration with the university of Groningen, Netherlands. The company is a technology provider developing chemical recycling technologies for different feedstocks including non-food bio- and plastics waste. In 2018 a pilot plant with the capability to process biomass and plastic waste was set up at the Zernike Advanced Processing (ZAP) Facility. The company is now focused on setting up their first commercial plant with a capacity of 20,000 to 30,000 tonnes. The investing phase B was recently completed, with the last investment phase in 2019 the financial requirements are fulfilled to complete the commercialisation activities to build the plant which is expected for 2023.''

describe their technology, here is an example

''The technology is based on an Integrated Cascading Catalytic Pyrolysis (ICCP) process, being able to produce aromatics including benzene, toluene, and xylene (BTX) as well as light olefins from low grade biomass and plastics waste. This technology utilises catalytic cracking in a two-step process at temperatures between 450- 850 °C. In the first step the feedstock material is vaporised via thermal cracking. The pyrolysis vapours are then directly passed into a second reactor in which they are converted into aromatics by utilising a zeolite catalyst which can be continuously regenerated. Finally, the products are separated from the gas via condensation. An ex situ approach of catalytic conversion has several advantages such as the protection of the catalyst from deactivation/degradation expanding its lifetime, a greater variety of feedstock, and a precise adjustment of process conditions (e.g. temperature, catalyst design, and Weight Hourly Space Velocity (WHSV) in each step for improved yields. In current pilot plant with 10 kg h-1 feed capacity for either waste plastics or biomass, final design details are established, which will be include in the running engineering activities for the commercial plant.''

=== Bio Base ===
Bio Base provides scale up of chromatography processes from lab-scale up to 4000 L scale. There is mainly a very broad knowledge of anion exchange, cation exchange and activated carbon processes, since (economically) those are most realistic to scale-up.

== Patents ==

==References==

[[Category:Hybrid processing]]