采用自催化乙醇法对蔗渣原料进行预处理,并通过傅里叶变换红外光谱、扫描电镜、X射线衍射仪对预处理样品进行分析,然后进行酶解.结果表明:蔗渣原料经乙醇预处理后,有大量木质素溶出和半纤维素水解;预处理样品的相对结晶度提高了32.97%;蔗渣纤维表面碎化,细小纤维暴露出来,极大地提高了酶解效率;当温度为195℃、乙醇体积分数为40%、保温时间为30min时,蔗渣原料木素去除率为57.97%,此时100g蔗渣原料经此预处理所得预处理液中的木糖量为8.59g,占原料中总木糖的35.16%,预处理样经酶解,所得酶解液中葡萄糖含量为40.29g,占原料中总葡萄糖的92.15%;初步实现了蔗渣原料中半纤维素和纤维素的逐步分离,同时得到大量乙醇木素;最优酶用量为10FPU/g(以每克固体浆料计),固液比为1∶40(g/mL).
Sugarcane bagasse was pretreated via the self-catalyzed ethanol delignification , and the pretreated sam-ples were analyzed by means of FT-IR, SEM and XRD , and then the corresponding enzymatic hydrolysis was made.The results show that (1) the pretreatment makes some lignin and hemicellulose hydrolyzed and the relative crystallinity of pretreated samples increases by 32.97%;(2) after the treatment, the surface of bagasse fibres is fragmented and fine fibres are exposed with a result that the efficiency of enzymatic hydrolysis is greatly improved ;(3) when the pretreatment is performed at the temperature of 195℃with a volume fraction of ethanol being 40%and warmth remaining for 30 min, 57.97% of lignin in the solid material are removed , and 8.59 g xylose is obtained from pre-hydrolyzate, which accounts for 35.16%of total xylose in the raw bagasse of 100 g;(4) during the subsequent enzymatic hydrolysis , 40 .29 g glucose is obtained , which accounts for 92 .15%of total glucose in the raw bagasse;(5) the gradual separation of hemicellulose and cellulose in raw material is preliminarily achieved and at the same time a large amount of ethanol lignin is obtained;and (6) the optimal enzyme dosage is 10 FPU/g and the solid-to-liquid ratio ( dry substrate ) is 1∶40 ( g/mL) .