无水硅酸钠催化酯交换合成碳酸二甲酯  

Synthesis of Dimethyl Carbonate via Transesterification Catalyzed by Anhydrous Sodium Silicate

作　　者：周喜[1,2] 李海燕[1] 李泽贤[1] 高雪萍[1] 张超[1] 王公应[2] 

机构地区：[1]邵阳学院生物与化学工程系,湖南邵阳422000 [2]中国科学院成都有机化学研究所,四川成都610041

出　　处：《精细化工》2015年第6期709-714,共6页Fine Chemicals

基　　金：湖南省自然科学基金(14JJ6045);湖南省教育厅优秀青年项目(14B161);国家高技术研究发展计划("863"计划;SS2013AA031703)~~

摘　　要：以廉价的Na2Si O3·9H2O为原料,通过简单的焙烧处理,制备了系列无水硅酸钠,并将其作为固体碱催化剂应用于碳酸乙烯酯（EC）与CH3OH酯交换合成碳酸二甲酯（DMC）的反应。采用TG-DTA、XRD和Hammett指示剂法对无水Na2Si O3进行表征。结果表明,焙烧温度对无水Na2Si O3的碱强度、总碱量及催化活性没有显著影响。当焙烧温度为200℃时,样品（Na2Si O3-200）的碱强度（Ho）为15.0-18.4,总碱量为10.9 mmol/g。以Na2Si O3-200为催化剂,考察了原料配比、温度和时间对酯交换合成DMC反应的影响。当CH3OH与EC的摩尔比为10∶1,在65℃反应2 h后,EC转化率与DMC收率可分别达到89%和88%。即使在室温条件下,Na2Si O3-200也能有效地催化EC与甲醇酯交换反应的进行。此外,经过4次使用后,Na2Si O3-200的催化活性没有出现明显下降的趋势。Anhydrous sodium silicate（ Na2 Si O3） was prepared by the simple calcination of Na2 Si O3·9H2O and used as solid base catalyst for the synthesis of dimethyl carbonate（ DMC） by transesterification of ethylene carbonate（ EC） with CH3 OH. Anhydrous Na2 Si O3was characterized by means of TG-DTA,XRD and Hammett indicator method. The results show that the calcination temperature has no significant effect on the basic strength,total basicity and catalytic activity of anhydrous Na2 Si O3. When the calcination temperature was 200 ℃,the basic strength（ Ho） of catalyst（ Na2 Si O3-200） was in the range of 15. 0 ~ 18. 4,and its total basicity was about 10. 9 mmol / g. The effects of raw material ratio,temperature and reaction time on the synthesis of DMC using Na2 Si O3-200 as catalyst were also investigated. The optimal molar ratio of CH3 OH to EC was 10 ∶ 1,and the conversion of EC could reach 89% with 88% DMC yield at 65 ℃ within 2 h. Na2 Si O3-200 could effectively promote the reaction even at room temperature. In addition,the catalytic activity of Na2 Si O3-200 has no remarkable decrease after 4 cycles.

关 键 词：碳酸二甲酯 碳酸乙烯酯 酯交换 固体碱催化剂 硅酸钠 精细化工中间体 

分 类 号：TQ225.5[化学工程—有机化工]