间歇萃取精馏分离碳酸二甲酯与甲醇恒沸物

Batch separation of dimethyl carbonate-methanol azeotrope

采用过程模拟与实验结合的方法,选用碳酸乙烯酯作萃取剂,采取间歇萃取精馏的方法研究回流比、萃取剂进料温度等对分离甲醇-碳酸二甲酯恒沸物的影响。结果表明,模拟结果与实验结果相比,优化了最佳操作条件。萃取精馏段回流比为0.8～1.2;最佳溶剂进料温度为64.5℃,溶剂进料量与共沸物的最佳摩尔比在1.85～1.95。优化的结果可以为工业放大研究提供基础,指导实验的进一步操作。

The aim of this work is to simulate and examine a batch extractive distillation process for purification of dimethyl carbonate （DMC） from the DMC-MEOH azeotropic system. The extractive solvent ethylene carbonate （EC） was used, which was also one of the reagents to synthesize DMC. The results of simulation were compared with examination in the following fields： reflux ratio, temperature of solvent, flow rate of solvent etc. The products could be separated under the following operation condition： reflux ratio in extractive distillation 0.8-1.2, reflux ratio in the distillation of EC-DMC 2-2.5; optimum temperature of solvent 65 ℃, flux rate of solvent to the azeotrope 1.85-1.95. The obtained results could be possibly used as the theoretical and practical basis for industrial equipment.