麦草纤维在甲酸体系中的水解动力学研究

The Kinetics Study of Wheat Straw Hydrolysis in Formic Acid System

研究麦草纤维在甲酸体系中的水解动力学;探讨甲酸体系中盐酸浓度、固液比、反应温度、反应时间对麦草纤维水解的影响以及在该体系中葡萄糖的降解情况;分析在该体系中葡萄糖的降解情况,结果表明,葡萄糖的降解反应和纤维素的水解反应相比是个快反应。麦草纤维素在φ=4%盐酸、甲酸体系中的水解速率60℃时为0.019 0 h-1,65℃时为0.032 5 h-1,70℃时为0.068 3 h-1,75℃时为0.093 1 h-1;葡萄糖的降解速率60℃时为0.028 5 h-1,65℃时为0.044 8 h-1,70℃时为0.109 8 h-1,75℃时为0.143 6 h-1。麦草纤维水解的Arrhenius方程指前因子为:9.12×1014h-1;葡萄糖降解的Arrhenius方程指前因子为:7.08×1015h-1。麦草纤维水解的表观活化能为106.35 kJ/mol;葡萄糖的降解表观活化能为111.00 kJ/mol。

Wheat straw was hydrolyzed with formic acid and hydrochloric acid under mild conditions. The effects of concentration of hydrochloric acid, the ratio of solid and liquor, temperature （60 -75℃ ） and retention time （0 - 9 h）, the concentration of glucose were analyzed. The degradation of glucose was also studied. The results indicated that the degradation of glucose was a fast reaction. The tendency was more obvious with the increase of temperature. The velocities of wheat straw hydrolysis were 0. 019 0 h^-1 at 60 ℃ , 0. 032 5 h^-1 at 65 ℃, 0. 068 3 h^-1 at 70 ℃, 0. 093 1 h^-1 at 75 ℃. The velocities of glucose degradation were 0.028 5 h^-1 at 60 ℃, 0.044 8 h^-1 at 65 ℃, 0. 109 8 h^-1 at 70 ℃, 0, 143 6 h^-1 at 75 ℃. The activation energy of microcrystalline cellulose hydrolysis was 106.35 kJ/mol; the activation energy of glucose degradation was 111.00 kJ/mol.