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采用浸渍法由凹凸棒石负载氧化镓(Ga2O3)制备了Ga2O3/凹凸棒石复合催化剂。用IR、XRD、BET、TEM对催化剂结构进行了表征,并通过肉桂酸环己酯的合成,对催化剂制备条件、催化活性和反应动力学特性进行了考察。结果表明:催化剂的最佳制备条件是Ga2O3负载量为催化剂总质量的10%,焙烧温度450℃;在肉桂酸环己酯合成过程中,当n(肉桂酸)∶n(环己醇)=1∶4.5(其中肉桂酸0.02 mol)、催化剂用量0.5 g、反应温度130℃、反应时间70 min时,产品平均酯化率为95.0%,催化剂经5次重复使用,酯化率仍达81.5%;反应为准二级反应,表观活化能为90.78 k J/mol,130℃时反应速率常数为1.03×10-2L/(mol·min)。
The Ga2O3 / attapulgite composite catalyst was prepared from the attapulgite loaded Ga2O3 by impregnation method. The structure of the catalyst was characterized by IR, XRD, BET and TEM. The preparation conditions, catalytic activities and reaction kinetics of cyclohexyl cinnamate were also investigated. The results showed that the optimum conditions for the preparation of catalyst were as follows: the loading of Ga2O3 was 10% of the total mass of the catalyst and the calcination temperature was 450 ℃; in the synthesis of cyclohexyl cinnamate, the molar ratio of n (cinnamic acid): n 1: 4.5 (cinnamic acid 0.02 mol), the amount of catalyst 0.5 g, the reaction temperature 130 ℃, the reaction time 70 min, the average esterification rate of the product was 95.0%. After five times of repeated use of the catalyst, the esterification rate still reached 81.5% The reaction was a quasi-second reaction with an apparent activation energy of 90.78 kJ / mol and a reaction rate constant of 1.03 × 10-2L / (mol · min) at 130 ℃.