【作者】 颜乐；

【导师】 朱志庆；

【作者基本信息】 华东理工大学 ， 化学工艺， 2011， 硕士

【摘要】 本文研究了乙二醇与甲醇一步氧化酯化制备乙醇酸甲酯的反应。首先进行催化剂的筛选实验,得到了具有良好催化活性的负载型Au/Al2O3催化剂,通过对反应条件的研究,确定了乙醇酸甲酯的最佳合成工艺条件。在催化剂的筛选阶段,首先考察了一系列Keggin型P-Mo-V杂多酸催化剂。实验结果表明,杂多酸催化剂对乙二醇与甲醇的氧化酯化反应没有催化活性。采用共沉淀法制备负载型Au/Al2O3催化剂,考察了不同Al203载体、Au负载量、催化剂制备过程中的焙烧温度等对反应转化率和选择性的影响。选用比较大的孔径Al203载体、Au负载量为0.5-1.0wt%、经过300℃焙烧2h制备的Au/Al2O3催化剂,显示出良好的催化活性和选择性。反应条件的研究结果表明,反应温度、压力、氧气浓度和原料配比等对反应转化率和选择性影响很大。适宜的反应条件为：反应温度120℃、反应压力0.45MP、氧气与氮气的分压比1：1-1：2、原料乙二醇和甲醇摩尔比为1：10,乙二醇的转化率和生成乙醇酸甲酯的选择性都达到80%以上。更多还原

【Abstract】 The preparation of methyl glycolate from ethylene glycol and methanol by one-step oxidative esterification was studied in this paper. Series of catalysts camparing experiments were carried out, which showed that Au/Al2O3 supported catalyst possessed good activity for the oxidative esterification. Based on the researches, the optimum reaction conditions for synthesis of methyl glycolate were determined.At first, the P-Mo-V heteropoly acids with Keggin structure were prepared and used for ethylene glycol oxidative esterification as a catalyst. Reaction results showed that these P-Mo-V heteropoly acid catalysts exhibited no activity. Then, Au/Al2O3 catalysts were prepared by deposition-precipitation method. The influences of Al2O3 grain size, quantity of Au loading and catalyst calcination temperature on the reaction conversion and selectivity were examined. The Au/Al2O3 catalyst prepared with large pore size support, Au weight loading between 0.5% and 1.0% and calcined under 300℃for 2h, showed favorable performance.The effects of reaction temperature, reaction pressure, oxygen concentration and raw material ratio were investigated. Both of the conversion of ethylene glycol and selectivity of methyl glycolate could reach up to 80% under the optimum conditions as follow:temperature at 120℃, pressure of 0.45 MPa (O2:N2=1:1～1:2) and the molar ratio of ethylene glycol to methanol equal to 1:10.更多还原