School of Chemical Engineering, Hebei University of Technology, Tianjin, 300130, China.
National-Local Joint Engineering Laboratory for Energy Conservation of Chemical Process Integration and Resources Utilization, Hebei University of Technology, Tianjin, 300130, China.
Bioprocess Biosyst Eng. 2020 Apr;43(4):593-604. doi: 10.1007/s00449-019-02250-2. Epub 2019 Nov 18.
The reactive distillation process for the synthesis of n-butyl acetate via transesterification of ethyl acetate with n-butyl alcohol catalyzed by immobilized lipase was simulated and experimentally tested in this work. Based on the reaction kinetics, a reactive distillation process model was developed. The effects of theoretical stages number in the reaction section, the rectifying section and stripping section, reflux ratio, feed molar ratio and relative feed position on the transesterification distillation process were investigated. The transesterification of ethyl acetate with n-butyl alcohol was carried out in a small-scale reactive distillation column. The results showed that the optimal operating conditions are as follows: reaction section stages were 13, rectifying section stages were six, stripping section stages were five, reflux ratio was 1, mole ratio of ethyl acetate and n-butanol was 3:1, the feeding positions of n-butanol and ethyl acetate were at the top and bottom of the reaction section, respectively. Compared to the batch reaction with only 60% conversion of n-butanol, the reactive distillation column can improve the conversion of n-butanol (up to 93.6%).At the same time, the experiment verified that the conversion of n-butanol could still reach 72.5%, after the lipase-loaded packing storage in the reaction system at 70 °C for 120 days.
本文对固定化脂肪酶催化乙酸乙酯与正丁醇的转酯化反应合成乙酸正丁酯的反应精馏过程进行了模拟和实验研究。基于反应动力学,建立了反应精馏过程模型。考察了理论塔板数在反应段、精馏段和提馏段、回流比、进料摩尔比和相对进料位置对酯交换精馏过程的影响。在小型反应精馏塔中进行了乙酸乙酯与正丁醇的转酯化反应。结果表明,最佳操作条件为:反应段 13 块理论塔板,精馏段 6 块理论塔板,提馏段 5 块理论塔板,回流比 1,乙酸乙酯与正丁醇的摩尔比为 3:1,正丁醇和乙酸乙酯的进料位置分别在反应段的顶部和底部。与仅 60%转化率的分批反应相比,反应精馏塔可以提高正丁醇的转化率(高达 93.6%)。同时,实验验证了在 70°C 下,固定化脂肪酶填充床在反应体系中储存 120 天后,正丁醇的转化率仍可达 72.5%。