Process For Extracting Lignin From Lignocellulosic Material Using An Aqueous Organic Solvent And An Acid Neutralizing Agent

A process for the delignification of cellulosic materials, wherein a high-yield cellulose pulp and high-value by-product, such as reactive lignins of low molecular weight are produced, which comprises degassing lignocellulosic material, rapidly heating the lignocellulosic material in a liquor comprising water, an organic solvent and a buffer thereby maintaining a substantially neutral solvent extraction, such that said lignocellulosic material is cooked in the liquor as it is heated from a temperature of 150°C. to a selected maximum temperature in the range of 200° to 280°C.; and rapidly cooling the mixture to a temperature less than 150°C. The reaction is controlled to maximize reactive lignin solvation while suppressing cellulose degradation.Georgia Tech Research Corp