以过量浸渍法制备了MgO-氢型丝光沸石复合催化剂,采用NH3-TPD和Py-IR手段对催化剂进行表征,并在100 mL三颈瓶中进行了柠檬酸与正丁醇的酯化反应测试催化剂性能.结果表明,当MgO在催化剂中的质量分数为0.5％时,催化剂具有较大的酸量,在反应温度110℃,反应时间90 min,醇酸摩尔比为5时,柠檬酸的转化率为96.4％,柠檬酸三丁酯的选择性达到98.2％.催化剂稳定性能好,使用4次后,柠檬酸的转化率维持在85％以上,柠檬酸三丁酯的选择性高于98％.%Composite catalysts MgOHM were made by an impregnation process and characterized by ammonia temperature programed desorption (NH3-TPD) and pyridine infrared spectroscopy (Py-IR) techniques. The catalytic performance was investigated for the esterification of citric acid with n-butyl alcohol in a 100 mL three-necked flask. The results of the characterization showed that 0. 5MgO-HM have highest acid amount when MgO mass ratio was 0. 5%. The reaction results showed that the suitable reaction temperature is 120 °C and the optimal reaction time is 90 min while the mole ratio of citric acid to M-butyl alcohol is 1 : 5. The catalytic performance of 0. 5%MgO-HM presented the highest activity, with the conversion of citric acid 96. I% and the selectivity of tirbutyl citrate 98. 2%. The stability tests showed that the conversion of citric acid and selectivity of tirbutyl citrate were 85. 9% and 98. 2% , respectively, after using 4 times.
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