酸水解法分离玉米芯中五碳糖和六碳糖的动力学

Kinetics of Dilute Acid Hydrolysis of Corn Cob for Pentose and Hexose Separation

以玉米芯为底物，采用间歇反应釜，在固液比为0．1g／mL，一定硫酸浓度（质量分数为0．1％～O．9％）和温度（130～170℃）下反应，建立酸水解动力学模型，通过非线性回归拟合获得模型参数。结果表明：较低温度和硫酸浓度可增大五糖碳收率和玉米芯中六碳糖保留率。合适的反应条件为130℃，H2S04的质量分数为O．1％，反应82min时，溶液中五碳糖浓度为36．2g／L，五糖碳收率为90．7％，玉米芯中戊聚糖水解率为97．6％，六碳糖保留率为96．9％。

Kinetic model of dilute acid hydrolysis was established with corn cob as substrate in a batch reactor under the operating conditions of, mass fraction of sulfuric acid of 0.1%-0.9%, solid to liquid ratio of 0.1 g/mL, and reaction temperature of 130-170 ℃. The nonlinear data regression method was used for the parameter fitting. The results showed that the pentose yield and hexose retain rate were favored at low reaction temperature and low acid concentration. Under the reaction temperature of 130℃, mass fraction of H2SO4 concentration 0.1%, and reaction time 82 rain, the pentose concentration was 36.2 g/L, the pentose yield reached 90.7%, the pentosan hydrolysis rate of corn cob was 97.6%, and the hexose retain rate was 96.9%.