碳酸钠预处理对麦草酶水解糖化的影响

摘要

Wheat straw is an important renewable lignocellulosic biomass,which is of great potential for bioethanol production.In this paper,sodium carbonate（SC） was used as pretreatment to improve the enzymatic hydrolysis of wheat straw.The effects of impregnation time,time at temperature,and Na2CO3 charge on the enzymatic hydrolysis of pretreated wheat straw were investigated.Extension of time at temperature has little effect on delignification,but lowers the pulp yield and total sugar recovery in enzymatic hydrolysis.An impregnation time of 30 min results relatively high sugar retention and enzymatic hydrolysis efficiency.Sodium carbonate charge plays an important role on improving lignin removal of wheat straw,and most carbohydrate retains.After wheat straw pretreated by sodium carbonate with 8% Na2CO3（as Na2O） at 130℃,the sugar recovery is 60% at a cellulase loading of 20 FPU/g cellulose.The results show that sodium carbonate pretreatment is a promising way to improve the enzymatic saccharification of straw materials.%麦草是一种具有很大潜力的制取生物乙醇的可再生木质纤维素原料。文章探讨了碳酸钠预处理预浸时间、保温时间、碳酸钠用量对麦草化学成分及酶水解效率的影响。结果表明,延长碳酸钠预处理保温时间对木质素脱除无明显影响,但浆料得率和酶水解总糖转化率有所下降;合理的预浸时间为30 min,继续延长预浸时间对预处理浆料酶水解总糖转化率无促进作用;增加预处理Na2CO3用量有助于促进木质素的脱除,大部分碳水化合物保留在浆料中。在8% Na2CO3（Na2O计）用量下,麦草于80℃预浸30 min后升温至130℃,不保温所得到的浆料在纤维素酶用量为20 FPU/g（对纤维素）时,其总糖转化率为60%。