Pretreatment of corncob residues in organic solvent and its effect on enzymatic digestibility

Solid residues from dilute acid pretreatment process of corncob may be used to produce liquor fuels and chemicals by bioconversion because of its high cellulose content,but its high lignin content leads to decrease of cellulose enzymolysis efficiency.The digestibility of enzyme can be improved by removal of lignin in lignocelluloses materials with some organic solvent.In this paper,pretreatment of corncob residues was carried out in ethanol solution and effect of process parameters(pretreatment temperature and time,ethanol concentration,ratio of solid to liquid)on chemical components and enzymatic digestibility was studied.The results showed lignin of 53.26% could be removed under pretreatment conditions of ethanol concentration 50%,210℃,ratio of solid to liquid 1∶8 and 60 min,and the conversion of cellulose to glucose increased from 69.84% to 84.42%.Compared with corncob residues,the pretreatment process was more effective for corn stover and corncob to remove lignin and increase enzymolysis efficiency of cellulose.