Patent ID: 8980595
Filing Date: 2015-03-17
Classification: C12P,Y02E,Y02P

Abstract:
1. A process of producing alcohol from a cellulosic or lignocellulosic substrate in which furfural is produced and which comprises at least the following steps: alkaline chemical pre-treating said substrate, comprising bringing the pre-treated and optionally washed substrate to a pH in the range 4.5 to 5.5, coupled with hydrolyzing by cellulolytic and/or hemicelluloytic enzymes, by enzymatic hydrolysis, said pre-treated substrate; fermenting with an alcohol-producing microorganism, by alcoholic fermentation, the resultant hydrolysate at the end of which a fermentation mash is obtained comprising material in suspension and a liquid phase comprising an alcohol and vinasses; then separating/purifying, at the end of which purified alcohol, clarified vinasses and an insoluble residue are obtained; converting, by acid conversion, at least one resultant liquid obtained during one of the preceding steps and containing dissolved pentoses, whereby a portion of said pentoses are converted into furfural; and mixing furfural obtained during the acid conversion step with the pre-treated substrate optionally washed during the pH adjusting step, the quantity of furfural mixed in being in the range 1 to 5 g/L with respect to the total quantity of liquid in the enzymatic hydrolysis step and/or the alcoholic fermentation step.