玉米芯稀酸预处理和分步糖化与发酵工艺生产燃料乙醇的中试研究

利用正交试验在中试水平考察了玉米芯的稀硫酸预处理和分步糖化与水解生产乙醇的工艺。结果:最佳预处理工艺为稀硫酸浓度1.1%,温度120℃,固液比1∶8,时间3 h;酶解糖化最佳工艺为:起始底物浓度180 g/L,滤纸酶活:纤维二糖酶活=20 IU/g底物:7 IU/g底物,pH=5.0,48 h;利用运动发酵单胞菌发酵酶解液,35℃,48 h,发酵液中乙醇浓度最高67.8 g/L。

Study on Fuel Ethanol Production from Corncob Using the Process of Dilute Acid Pretreatment and Separated Saccharification and Fermentation

The goal of this study is to achieve the optimum process parameters for fuel ethanol production at pilot scale from corncob feedstock.After the optimization of orthogonal experiment,the process configuration including dilute acid pretreatment and separated saccharification and fermentation（SHF） has been obtained： the optimum parameters of pretreatment process are at 120 ℃ for 3 h with 1.1 % sulphuric acid as well as solid-to-liquid ratio=1：8,and the optimum condition of enzymatic hydrolysis are at initial pH 5.0 and 48 ℃ for 48 h with FPA： CBA=20： 7（IU/g substrate）.The maximum ethanol consistency in the fermentation broth of enzymatic hydrolyzates by Zymomonas mobilis at 35 ℃ for 48 h is 67.8 g/L from 180 g/L substrate produced by pretreatment.