INTEGRATED BIOREFINERIES FOR PRODUCTION OF SUGARS, FERMENTATION PRODUCTS, AND COPRODUCTS

摘要

Processes are described for fractionating lignocellulosic biomass into cellulose, hemicellulose, and lignin, comprising fractionating lignocellulosic biomass in the presence of a solvent for lignin (such as ethanol), a hydrolysis catalyst (such as sulfur dioxide), and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; hydrolyzing the hemicellulose to produce hemicellulosic monomers; saccharifying the cellulose-rich solids to produce glucose; recovering the hemicellulosic monomers and the glucose, separately or in a combined stream, as fermentable sugars; and fermenting the fermentable sugars to a fermentation product having a higher normal boiling point than water. Process integration of mass and/or energy is disclosed in many specific embodiments. The fermentation product may include an organic acid, an alcohol, a diol, or combinations thereof.

主权项

1. A process for fractionating lignocellulosic biomass into cellulose, hemicellulose, and lignin, said process comprising:
(a) in a digestor, fractionating a feedstock comprising lignocellulosic biomass feedstock in the presence of a solvent for lignin, a hydrolysis catalyst, and water, to produce a liquor containing hemicellulose, cellulose-rich solids, and lignin; (b) substantially separating said cellulose-rich solids from said liquor; (c) hydrolyzing said hemicellulose contained in said liquor to produce hemicellulosic monomers; (d) recovering said hemicellulosic monomers as fermentable sugars; (e) fermenting at least a portion of said fermentable sugars to a fermentation product having a relative volatility with water of less than 1.0; and (f) recovering said fermentation product, wherein said process includes process integration of mass and/or energy between at least two of steps (a)-(f).