【摘要】 以玉米秸秆为原料,研究了中酸预处理条件下水洗得到的残渣经酶水解后进行己糖发酵、水洗液经三烷基胺萃取脱毒后进行戊糖发酵的乙醇得率,并对整个工艺进行了物料衡算。结果表明:中酸预处理的最佳条件为温度100℃,硫酸质量分数3%,时间12 h。残渣的酶水解液浓缩至葡萄糖质量浓度为138.72 g/L进行乙醇发酵,在24 h时糖利用率为99.02%,此时乙醇质量浓度达到最高为62.98 g/L,是乙醇理论得率的89.90%。水洗液经过三烷基胺萃取脱毒后,乙酸、5-羟甲基糠醛和糠醛的去除率分别为72.73%、42.86%和100%;水洗液经浓缩、脱毒后的脱毒液(含有7.80 g/L葡萄糖和52.80 g/L木糖)的乙醇发酵能力大大提高,在48 h时糖利用率为93.17%,此时乙醇质量浓度达到最高为21.76 g/L,是乙醇理论得率的82.34%。经物料衡算,生产1 t乙醇需要6.8 t绝干玉米秸秆。该工艺为实现己糖和戊糖分开发酵的工业化提供参考依据。更多还原

【Abstract】 Corn stover was pretreated by moderate acid and then washed by water.The solid residue after filtration was hydrolyzated to monosaccharide with cellulase for further fermentation to ethanol,while the liquid fraction after filtration was detoxified with trialkylamine extraction to ferment to ethanol.The material balance was carried out in the whole process.The results showed that the optimal pretreatment conditions were temperature 100 ℃,sulfuric acid mass fraction 3 % and time 12 h.After 24 h fermentation of the condensed enzymatic hydrolyzate containing 138.72 g/L of glucose,the sugar utilization rate was 99.02 % and the ethanol mass concentration reached its peak value of 62.98 g/L,which corresponded to 89.90 % of the theoretical value.Prehydrolyzate was detoxified by trialkylamine extraction,72.73 % of acetic acid,42.86 % of 5-hydroxymethylfurfural and 100 % furfural could be removed.The fermentability of the detoxified prehydrolyzate was significantly improved.After 48 h fermentation of the detoxificated prehydrolyzate containing 7.80 g/L of glucose and 52.80 g/L of xylose,the sugar utilization rate was 93.17 %,and the ethanol concentration reached its peak value of 21.76 g/L,which corresponded to 82.34 % of the theoretical value.After materials balance,it required 6.8 t absolutely dry corn stover to produce one ton ethanol.The process of this study provided the reference to realize the industrialization of hexose and pentose fermentation separately.更多还原