METHOD OF RENDERING LIGNIN SEPARABLE FROM CELLULOSE AND HEMICELLULOSE IN LIGNOCELLULOSIC MATERIAL AND THE PRODUCT SO PRODUCED

摘要

TITLEA METHOD OF RENDERING LIGNIN SEPARABLE FROM CELLULOSEAND HEMICELLULOSE IN LIGNOCELLULOSIC MATERIAL ANDTHE PRODUCT SO PRODUCEDINVENTOREdward A. DeLongABSTRACT OF THE DISCLOSURELignocellulosic material is packed in particulateform in a pressure vessel, steam is passed into the pressurevessel at a pressure of at least 500 psi to bring the ligno-cellulosic material to a temperature in the range 185 to 240°C(preferably in the range 200 to 238°C, more particularly 234°C)in less than 60 seconds (preferably less than 45 seconds) toplasticize the lignocellulosic material. As soon as the ma-terial is plasticized it is extruded through a die to atmo-sphere where abrasion in the die and explosive decompressionforms a particulate material like potting soil that rapidlysinks in water and from which the cellulose content is large-ly utilizeable, e.g. as a feed for ruminants. During extru-sion the softened material is subjected to severe deformationand then severe mechanical shock thus fracturing the linkagesbetween lignin, the hemicellulose and the cellulose. Thetemperature range and rapid rise thereto by the materialsubstantially minimizes degradation of the fragile hemicellu-lose. The process according to the present invention con-verts lignocellulosic material into a substrate which isextremely easy to treat by enzymes, either as a feed forruminant animals or for conversion to sugars and alcoholsand for the solvent extraction of lignin.