Скачать с ютуб Pretreatment and Enzymatic Hydrolysis of Lignocellulosic Biomass в хорошем качестве

Pretreatment and Enzymatic Hydrolysis of Lignocellulosic Biomass

Why Pre-treatment is Necessary? In the hydrolysis process cellulose and hemicellulose are hydrolysed (broken apart) in pure water through attack by the hydrogen atoms of the water molecule on these polysaccharides. This is a very slow reaction, particularly for cellulose due to its recalcitrance to hydrolysis, but it can be sped up using elevated temperatures and pressures, and catalysed by acids (concentrated or dilute) and highly selective enzymes such as cellulases. However, the rates of hydrolysis of cellulose when processing virgin biomass are still very low due to the recalcitrance of the lignocellulosic matrix. In particular, the complex inter-associations between hemicellulose and cellulose, the crystalline nature of much cellulose, and the existence of a physical barrier of lignin surrounding the cellulose fibres are said to be major hindrances. Biomass is more than just cellulose, however, and the process is complicated by the relative ease with which hemicellulose can be hydrolysed meaning that a severe means of hydrolysis targeted for the liberation of glucose from cellulose may result in the sugars liberated from hemicellulose being degraded. For these, and other, reasons most hydrolysis technologies involve a pretreatment step prior to the hydrolysis of the cellulose. This typically targets the removal of hemicellulose and/or lignin, leaving a solid predominately cellulosic residue that is more amenable to conversion. The hemicellulose is typically present in the liquid output from the pretreatment and can be valorised in separate processes. To learn more: https://www.celignis.com/analysis-to-... About Celignis We are dedicated to the development of innovations for our clients related to the use and valorisation of biomass and wastes. This is enabled through our state-of-the-art laboratories, equipment, and highly qualified personnel. Whether you need sample analysis or the development of a full process for the production of commercially relevant products, our top-class multi-disciplinary team of scientists and business leaders can help. Follow us on our social media:   / celignis-limited     / celignis     / celignisanalytical