玉米芯氨水预处理及酶解工艺研究

为有效提高木质纤维素酶解转化率,文中以玉米芯为研究对象,在常压中温下采用氨水浸泡工艺处理原料,考察了预处理条件对木质素脱除率和纤维素、半纤维素酶解转化率的影响规律。确定了最适预处理条件:氨水质量分数为15%、固液质量体积比为1∶6 g/mL、反应温度为60℃和预处理时间为12 h。该条件下纤维素、半纤维素回收率和木质素脱除率分别为94.5%,86.7%和48.1%;在每g葡聚糖加入30 FPU纤维素酶和60 CBUβ-葡萄糖苷酶条件下,酶解24 h后纤维素和半纤维素酶解转化率分别可达83.0%和81.6%。

Aqueous ammonia pretreatment and enzymatic hydrolysis of corn cobs

To effectively improve the enzymatic digestibility of carbohydrates in lignocellulose,the effect of the pretreatment conditions on the delignification and enzymatic digestibility was discussed with corn cobs as the investigated object and the feedstock soaking in aqueous ammonia under the modest conditions.The optimum pretreatment conditions were determined as follows: aqueous ammonia mass fraction 15%,solid to liquid ratio(mass/volume) 1 ∶6 g/mL,reaction temperature 60 ℃ and pretreatment time 12 h.Under such conditions,the recovery ratio of cellulose,hemicelluloses and the delignification ratio can reach 94.5%,86.7% and 48.1%,respectively.The enzymatic digestibility of cellulose hemicellulose can attain 83.0% and 81.6% respectively under the condition of per gram of glucan loaded with 30 FPU/g-glucan cellulase and 60 CBU/g-glucan β-glucosidase and after enzymatic hydrolysis for 24 h.