2,3-丁二醇分离纯化中反应精馏的实验和模拟

Experiment and Simulation of Reactive Distillation for 2,3-butanediol Separation from Fermentation Broth

对反应萃取-水解精馏法分离发酵液中2,3-丁二醇工艺中的水解精馏进行了实验和模拟研究。实验验证了4,5-二甲基-2-丙基-1,3-二氧戊环(DPD)水解精馏得到2,3-丁二醇的可行性。采用Aspen Plus建立反应精馏模型,以UNIFAC为热力学方程,RadFrac为反应精馏模块,对常压下DPD的水解精馏进行模拟,模拟结果与实验结果吻合较好。以2,3-丁二醇的收率为主要优化目标,考察最佳塔板数、进料位置、进料比、回流比和塔顶馏出比。模拟结果表明,在最佳操作条件下,塔釜2,3-丁二醇的收率为0.981,摩尔分率为0.150。

The hydrolysis distillation for separation of 2,3-butanediol from fermentation broth by reactive extraction-hydrolysis distillation method was studied by experiment and simulation.The feasibility of 4,5-dimethyl-2-propyl-1,3-dioxolane(DPD) hydrolysis in reactive distillation column was investigated by experiment and the model of reactive distillation was established by Aspen Plus.UNIFAC equation was used as thermodynamics method and RadFrac module was applied.The results of simulation were fitted with experiment which implied that the model was reliable.Hydrolysis distillation column was designed on the basis of the established model.Appropriate stage number,feed stage,ratio of water to oil in feed,reflux ratio and ratio of distillate to feed were determined.Under the optimum operate conditions,0.981 of 2,3-butanediol yield at bottom and 0.15 of 2,3-butanediol molar fraction at bottom could be obtained while the reboiler duty was low.