赵雪冰，刘德华

清华大学化学工程系应用化学研究所，北京 100084

乙酸分级预处理甘蔗渣对纤维素酶解性能的影响

赵雪冰，刘德华

清华大学化学工程系应用化学研究所，北京 100084

为提高甘蔗渣的纤维素酶解性能，采用乙酸脱木素结合碱脱乙酰基的预处理工艺 (Acetoline工艺) 对甘蔗渣进行预处理，考察了乙酸脱木素过程中若干因素对预处理结果的影响，并对预处理后甘蔗渣的纤维素酶解性能进行了研究。结果表明，经过Acetoline预处理后甘蔗渣在7.5%固体含量、15 FPU+10 CBU/g固体的纤维素酶和β-葡萄糖苷酶用量下酶解48 h，酶解聚糖转化率接近80%。与稀酸预处理相比，Acetoline预处理可以得到更高的酶解聚糖转化率。实验结果表明Acetoline工艺是一种可有效提高甘蔗渣纤维素酶解性能的预处理方法。

木质纤维素，预处理，酶解性能，脱木素，脱乙酰基

Abstract:During the bioconversion of lignocellulose to ethanol, the biomass always undergoes pretreatment in order to increase the enzymatic digestibility of cellulose. In present work, we conducted the pretreatment of sugarcane bagasse with aqueous acetic acid for delignification and alkali for deacetylation respectively (Acetoline process) to increase cellulose accessibility for enzymatic hydrolysis. The effects of several factors on the pretreatment effectiveness were investigated. The enzymatic digestibility of pretreated bagasse was further studied. The enzymatic glycan conversion of pretreated solid reached about 80% when it was digested under 7.5% solid consistency with cellulase of 15 FPU/g solid and β-glucosidase of 10 CBU/g solid for 48 h. Compared with dilute acid pretreatment, Acetoline pretreatment could obtain higher enzymatic glycan conversion. The experimental results indicate that Acetoline is an effective pretreatment method to increase the enzymatic digestibility of sugarcane bagasse.

Keywords:lignocellulose, pretreatment, enzymatic digestibility, delignification, deacetylation

近年来，从木质纤维素生物转化生产燃料乙醇的研究与开发受到了世界各国的广泛关注。这一方面是由于乙醇与汽油混合后可提高汽油的辛烷值和含氧量，使得汽油能够更加完全地燃烧，从而减少颗粒污染物及CO等气体的排放[1]。另一方面是由于乙醇不仅可以由淀粉质原料发酵生产，还可以由来源广泛且价格低廉的木质纤维素生产。据估计，地球上每年光合作用的产物 (生物质) 高达1 500~2 000亿t，是地球上唯一可超大规模再生的实物性资源[2]。同时，全生命周期分析表明纤维素乙醇生产可以显著降低 CO2的净排放量[3]。但由于木质纤维素的致密性和木质化结构阻碍了纤维素的酶催化水解。……