Hydrolysis
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 in which water is the nucleophile.[1] In lignocellulosic biomass, the cellulose and hemicellulose breaks down into individual sugars, where hemicellulose is easier to hydrolyse than cellulose.[2] The result of hydrolysing hemicellulose and cellulose is sugars (glucose, xylose, mannose, and galactose) and organic acids (formic acid and acetic acid).[3]
Feedstock
Biowaste lorum ipsum
Process and technologies
Acid
Acid hydrolysis is a hydrolysis process in which a protic acid is used to catalyze the hydrolysis reaction. A Dilute acid pretreatment only hydrolyses the hemi-cellulose, which makes the cellulose more susceptible for enzymatic conversions. The biowaste is immersed in a diluted form of strong acids, such as sulphuric acid, at elevated temperatures.[4]
Alkali
Alkaline hydrolysis refers to types of nucleophilic substitution reactions in which the attacking nucleophile is a hydroxide ion.
Salt
Hydrolysis can be further improved by the addition of 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.[4]
Sulphite salt
Lorum ipsum
Solvent
Solvents can be added to improve the hydrolysis process.
Organosolv
In an organosolv hydrolysis organic solvents are added to the process. For example, in acid-acetone pre-treatment biowaste is treated with an acid such as phophoric acid and then mixed with pre-cooled acetone to allow for a cold shock.[4]
Product
Lorum ipsum
Technology providers
[space for technology comparison]
Valmet Oyj
| General information | |||
| Company: | Valmet Oyj | 
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| Country: | |||
| Contact: | |||
| Webpage: | https://www.valmet.com/ | ||
| Technology and process details | |||
| Technology name: | BioTrac | Technology category: | Conversion (Thermochemical processes and technologies) |
| TRL: | 9 | Capacity: | biomass feed up to 800 tonne/day kg·h-1 |
| Atmosphere: | Catalyst: | Acid conditions | |
| Heating: | Pressure: | Up to 25 bar bar | |
| Reactor: | Horizontal tube reactor | Temperature: | High temperature °C |
| Other: | |||
| Feedstock and product details | |||
| Feedstock: | All lignocellulosic biomass, including wood and forest residues, wheat straw, corn stover and bagasse | Product: | |
Patents
Lorum ipsum
References
- ↑ Wikipedia, 2002: Hydrolysis 2002, Last access 2021. https://en.wikipedia.org/wiki/Hydrolysis
- ↑ P. Lenihan, A. Orozco, E. O’Neill, M.N.M. Ahmad, D.W. Rooney, G.M. Walker, 2010-01-15: Dilute acid hydrolysis of lignocellulosic biomass. Chemical Engineering Journal, Vol. 156, (2), 395–403. doi: https://doi.org/10.1016/j.cej.2009.10.061
- ↑ Katarzyna Świątek, Stephanie Gaag, Andreas Klier, Andrea Kruse, Jörg Sauer, David Steinbach, 2020-04-17: Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation. Catalysts, Vol. 10, (4), 437. doi: https://doi.org/10.3390/catal10040437
- ↑ a b c Amit K. Jaiswal, Rajeev Ravindran, 2016-01-01: A comprehensive review on pre-treatment strategy for lignocellulosic food industry waste: Challenges and opportunities. Bioresource Technology, Vol. 199, 92–102. doi: https://doi.org/10.1016/j.biortech.2015.07.106