和稀盐酸联合催化下的水解动力学研究

以微晶纤维素为原料,在1 g/L的FeCl3存在下和2%的盐酸溶液体系中进行水解,根据水解属于串联反应的特点,研究了微晶纤维素在H+和Fe3+共同作用下的水解动力学规律。研究采用目标物产率与模型函数值残差(S)为最小确定模型函数,对实验数据进行了处理。结果表明:H+和Fe3+共同作用能显著降低纤维素水解和葡萄糖降解的活化能。其中,纤维素水解成为葡萄糖的活化能为81.70 kJ/mol,葡萄糖降解成为小分子的活化能为43.85 kJ/mol,在温度为130、140和150℃时,纤维素水解速率常数分别为0.041 4、0.073 2和0.115 3 h-1,相应温度下葡萄糖降解速率常数分别为0.205 3、0.242 4和0.356 5 h-1。

Hydrolysis Kinetics of Microcrystalline Cellulose Catalyzed by Fe3+ and Dilute Hydrochloric Acid

The microcrystalline cellulose was hydrolyzed in the presence of 1 g/L FeCl3 and 2% hydrochloric and the hydrolysis kinetics was investigated in this study.According to the principle of minimum of residue error S between actual yields of glucose and calculated value from the established function,the objective function is selected.The results indicated that the activation energy of the hydrolysis reaction for microcrystalline cellulose and glucose can be significantly reduced due to the presence of H + and Fe3 +.For the hydrolysis reaction of microcrystalline cellulose and glucose,the activation energy is 81.70 kJ/mol and 43.85 kJ/mol,respectively.The hydrolysis constant rate of microcrystalline cellulose is 0.041 4,0.073 2 and 0.115 3 h-1 at the temperature of 130,140 and 150 ℃,respectively.For glucose,it is 0.205 3,0.242 4 and 0.356 5 h-1 at the corresponding temperatures.