碳酸二甲酯和乙醇酯交换法制备碳酸二乙酯的工艺研究  

Process Study on Preparation of Diethyl Carbonate by Transesterification of Dimethyl Carbonate and Ethanol

作　　者：王真贝 钱赟 WANG Zhen-bei;QIAN Yun(Jiangsu Yangnong Chemical Group Co.,Ltd.,Jiangsu Yangzhou 225001,China)

机构地区：[1]江苏扬农化工集团有限公司,江苏扬州225001

出　　处：《广州化工》2022年第13期86-89,共4页GuangZhou Chemical Industry

摘　　要：研究了采用酯交换法合成碳酸二乙酯(DEC)的不同催化剂的性能,考察了催化剂浓度、物料配比、反应温度、回流比等工艺条件对反应的影响。通过实验,确定了乙醇与碳酸二甲酯(DMC)液相酯交换合成碳酸二乙酯的最佳反应条件。由于碳酸二乙酯、碳酸甲乙酯(EMC)均具有较好的市场,因此本文并未一味地追求碳酸二乙酯的高选择性,而是创新性的采用选择性在50%左右的甲醇钠作为催化剂,乙醇对碳酸二甲酯的摩尔比例为1.1,催化剂量为总原料质量的1.5%,反应温度为75~85℃,反应时间为4 h,反应精馏的回流比为5:1,DMC的转化率达到了70%左右,DEC的选择性达到了45%左右,DEC的产率达到了35%左右。并对催化剂的回收再利用可行性进行了实验研究,重复4次后,催化剂性能没有明显下降,说明了催化剂回收再利用的可行性。The properties of different catalysts for the synthesis of diethyl carbonate(DEC)by transesterification were studied.The effects of catalyst concentration,material ratio,reaction temperature and reflux ratio on the reaction were investigated.The optimum reaction conditions for the synthesis of diethyl carbonate by liquid phase transesterification of ethanol and dimethyl carbonate(DMC)were determined.As both diethyl carbonate and methyl ethyl carbonate(EMC)had a good market,the high selectivity of diethyl carbonate did not blindly pursued,but innovatively adopted sodium methoxide with selectivity of about 50%as the catalyst,the molar ratio of ethanol to dimethyl carbonate was 1.1,the amount of catalyst was 1.5%of the total raw material mass,the reaction temperature was 75~85℃and the reaction time was 4 h.The reflux ratio of reactive distillation was 5:1,the conversion of DMC was about 70%,the selectivity of Dec was about 45%,and the yield of Dec was about 35%.The feasibility of catalyst recovery and reuse was experimentally studied.After four repetitions,the catalyst performance did not decline significantly,indicating the feasibility of catalyst recovery and reuse.

关 键 词：酯交换 碳酸二乙酯 转化率 选择性 

分 类 号：O69[理学—化学]