Fuel ethanol production from lignocellulosic biomass corn stover was investigated. Compared with acid pretreatment and ammonia steeping pretreatment, alkali pretreatment with 2% NaOH markedly enhanced lignin removal and thereby improved the enzymatic hydrolysis yield to 81.2% by 48 h. Fed-batch hydrolysis was started with a batch hydrolysis containing 80 g/l substrate, with cellulosic residue added at 6 and 12 h twice to get a final substrate concentration of 110 g/l. After 72 h of hydrolysis, the reducing sugar concentration reached 89.5 g/l with a hydrolysis yield of 83.3%. Further fermentation of the cellulosic hydrolysate containing 56.7 g/l glucose and 23.6 g/l xylose was performed using a recombinant yeast strain Saccharomyces cerevisiae ZU-10, and 36.3 g/l ethanol was produced within 72 h. The research results are meaningful in fuel ethanol production from renewable lignocellulosic biomass.
Biochemical Conversions of Lignocellulosic Biomass for Sustainable Fuel-Ethanol Production in the Upper Midwest
