烷氧基化法一步合成乙二醇甲醚苯甲酸酯的研究

One-step synthesis of ethylene glycol monomethyl ether benzoate by alkoxylation

采用镁铝锰固体催化剂催化环氧乙烷开环并插入苯甲酸甲酯(MB)的酯键中一步合成乙二醇甲醚苯甲酸酯(EGMB),研究了催化剂中镁铝锰金属阳离子的摩尔比、催化剂焙烧温度等对催化剂活性的影响,采用SEM分析催化剂形貌特征,经FTIR表征确认目标产物为EGMB。同时优化了烷氧基化法一步合成乙二醇甲醚苯甲酸酯的工艺条件。研究结果表明:在n(Mg^(2+))∶n(Al^(3+))∶n(Mn^(2+))=1∶1∶0.04,焙烧温度为400℃的条件下,制备的催化剂活性最高;在苯甲酸甲酯与环氧乙烷摩尔比为3∶1,反应温度为120℃,催化剂质量为原料总质量的1.5%的条件下,EO转化率为86.40%,EGMB的产率为47.00%,DEGMB的产率为25.95%,TEGMB的产率为9.84%。

One-step ethoxylation reaction catalyzed by Al-Mg-Mn composite oxide is used to synthesize ethylene glycol monomethyl ether benzoate（ EGMB） by inserting ethylene oxide（ EO） into methyl benzoate（ MB）. The influences of catalyst preparation conditions on catalyst activity have been investigated and the process conditions have been optimized. Surface morphology of catalysts is determined by scanning electron microscope. The chemical structure of the product is characterized by FTIR. The optimal conditions are shown as follows： 1 ∶ 1 ∶ 0. 04 molar ratio of n（ Mg^2＋/Al^3＋/ Mn^2＋）,400℃ of calcination temperature,3∶ 1 molar ratio of MB/EO,120℃ of reaction temperature and 1. 5% of catalyst. Under the optimal condition,the conversion of is 86. 40%. The yield of EGMB,DEGMB and TGMB is 47. 0%,25. 95% and TGMB,respectively.