PROCESS FOR THE PRODUCTION OF ALCOHOLS FROM BIOMASS

摘要

Alcohols useful as fuel compositions are produced from biomass by: contacting the biomass with a cooking liquor containing (i) 1 to 20 wt %, based on the cooking liquor, of sodium hydroxide, (ii) optionally, 0 to 20 wt %, based on the cooking liquor, of sodium sulfide; (iii) optionally, 0 to 3%, based on the cooking liquor, of anthraquinone, sodium borate and/or polysulfides; and (iv) water, wherein such cooking liquor has an active alkali of between 5 to 25%, and a sodium carbonate concentration of less than 3.5 wt% based on cooking liquor, at a cooling liquor to biomass ratio within the range of 2 to 6, at a temperature within the range of 1000C to 2300C with a residence time within 0.25 h to 4h under conditions effective to provide a pulp stream containing pulp having a lignin content of 5% to 20% by weight, based on the pulp, and a chemical liquor stream containing sodium compounds; washing the pulp stream with a water stream producing washed pulp stream; hydrolyzing the washed pulp stream by treating the streams with an enzyme solution comprising cellulases and optionally xylanases at a pH within the range of 3 to 7 at a temperature within the range of 300C to 900C to produce a hydrolyzate containing from 4% to 30% by weight of fermentable sugar; fermenting the hydrolyzate in the presence of a microorganism at a temperature with the range of 250C to 550C at a pH within the range of 4 to 6 thereby producing an alcohol stream containing at least one alcohol having 2 to 18 carbon atoms.