AQUEOUS FRACTIONATION OF BIOMASS BASED ON NOVEL CARBOHYDRATE HYDROLYSIS KINETICS

摘要

A multi-function process for hydrolysis and fractionation of lignocellulosic biomass to separate hemicellulosic sugars from other biomass components comprising extractives and proteins; a portion of a solubilized lignin; cellulose, glucose derived from cellulose; and insoluble lignin from said biomass comprising: a) introducing either solid fresh biomass or partially fractioned lignocellulosic biomass material with entrained acid or water into a reactor and heating to a temperature of up to about 185°C-205°C; b) allowing the reaction to proceed to a point where about 60 % of the hemicellulose has been hydrolyzed in the case of water or complete dissolution in case of; c) adding a dilute acid liquid at a pH below about 5 at a temperature of up to about 205 °C for a period ranging from about 5 to about 10 minutes; to hydrolyze the remainging 40 % of hemicellulose if water is used; d) quenching the reaction at a temperature of up about 140 °C to quench all degradation and hydrolysis reactions; and e) introducing into said reaction chamber and simultaneously removing from said reaction chamber, a volumetric flow rate of dilute acid at a temperature of up to about 140 °C to wash out the majority of the solubilized biomass components, to obtain improved hemicellulosic sugar yields.