PROCESSES FOR CO-PRODUCING XYLITOL WITH ETHANOL OR OTHER FERMENTATION PRODUCTS

摘要

What is disclosed is a biorefining process to co-produce xylitol with ethanol or other products. In some variations, a process for producing ethanol and xylitol from lignocellulosic biomass, comprises: extracting hemicelluloses from lignocellulosic biomass, wherein the hemicelluloses include xylose oligomers and other sugar oligomers; hydrolyzing the xylose oligomers and the other sugar oligomers, using an acid catalyst or enzymes, to generate xylose and other sugar monomers, respectively; fermenting the other sugar monomers to ethanol using a suitable ethanol-producing microorganism; removing at least some of the ethanol (to increase concentration of xylose); fermenting the xylose to xylitol using a suitable xylitol-producing microorganism; and recovering the xylitol at high concentration.

主权项

1. A process for producing xylitol and another fermentation product from lignocellulosic biomass, said process comprising:
(a) extracting hemicelluloses from a feedstock comprising lignocellulosic biomass, wherein said hemicelluloses include xylose oligomers and other sugar oligomers; (b) hydrolyzing said xylose oligomers and said other sugar oligomers, to generate xylose and other sugar monomers, respectively, using an acid catalyst or enzymes; (c) fermenting said other sugar monomers to a first fermentation product, using a suitable first microorganism; (d) optionally removing at least some of said first fermentation product; (e) fermenting said xylose to a second fermentation product comprising xylitol, using a suitable second microorganism; (f) recovering said first fermentation product, derived from step (c) and/or, if conducted, step (d); and (g) recovering said xylitol derived from step (e).