PROCESSES FOR PRODUCING LEVULINIC ACID FROM BIOMASS

摘要

This invention provides processes to convert biomass, including wood and agricultural residues, to levulinic acid and co-products. Some variations treat feedstock with steam and/or hot water to produce an extract liquor containing hemicellulosic oligomers, lignin, and cellulose-rich solids, wherein the hemicellulosic oligomers comprise C5 hemicelluloses and C6 hemicelluloses; separate the cellulose-rich solids from the extract liquor, to produce dewatered solids containing cellulose and lignin; dehydrate the hemicellulosic oligomers to convert the C6 hemicelluloses directly to 5-hydroxymethylfurfural; and convert the 5-hydroxymethylfurfural to levulinic acid. Also, the cellulose may be dehydrated directly to 5-hydroxymethylfurfural, which may then be converted to additional levulinic acid. Various biorefinery embodiments are disclosed, in which C5 and C6 sugars are processed separately or in combination.

主权项

1. A process for producing levulinic acid from cellulosic biomass, said process comprising:
(a) providing a feedstock comprising cellulosic biomass; (b) providing an extraction solution comprising steam and/or hot water; (c) treating said feedstock with said extraction solution under effective extraction conditions to produce an extract liquor containing hemicellulosic oligomers, lignin, and cellulose-rich solids, wherein said hemicellulosic oligomers comprise C5 hemicelluloses and C6 hemicelluloses; (d) separating at least a portion of said cellulose-rich solids from said extract liquor, to produce dewatered solids containing cellulose and lignin; (e) dehydrating said hemicellulosic oligomers under effective dehydration conditions to convert at least a portion of said C6 hemicelluloses directly to 5-hydroxymethylfurfural; (f) converting at least some of said 5-hydroxymethylfurfural to levulinic acid; and (g) recovering said levulinic acid.