Method for producing ethanol from lignocellulosic raw material

Abstract

The present invention provides a method for producing ethanol with an improved flow rate of permeation in membrane separation. More specifically, the present invention provides a method for producing ethanol from a lignocellulosic raw material, comprising a first step of performing saccharification and fermentation in a reaction system containing a lignocellulosic raw material, a saccharification enzyme, a yeast, and water, thereby producing ethanol; and a second step of treating, with a separation membrane, a first mixture containing the ethanol, water, the yeast, the saccharification enzyme, and a reaction residue of the lignocellulosic raw material, obtained in the first step, thereby obtaining a mixture containing the ethanol and water, and a second mixture containing the yeast, the saccharification enzyme, water, and the reaction residue of the lignocellulosic raw material; wherein the concentration of suspended solids in the first mixture is from 4 to 9.5% by mass.

Dependencies are inferred from the claim text.