SEPARATION OF REACTIVE CELLULOSE FROM LIGNOCELLULOSIC BIOMASS WITH HIGH LIGNIN CONTENT
A process for separating the components of lignocellulosic biomass for the purpose of producing a pure reactive cellulose is disclosed. The process has two stages. In the first stage, the lignocellulosic biomass is pretreated with steam, with or without an acid catalyst and then pressed, with or without the presence of an eluent. to remove hemicellulose and other impurities. In the second stage, the pretreated biomass is extracted with a solvent such as ethanol with or without acid catalysts in order to remove lignin and release a purified cellulose stream. The extracted cellulose is then rapidly decompressed to rupture the fibrous structure. The process provides a purified cellulose stream that is relatively easy to hydrolyze with enzymes and ferment to biofuels and other chemicals such as ethanol.