KF/γ-Al2O3催化酯交换反应精馏的研究

Study on transesterification reactive distillation catalyzed by KF/γ-Al2O3

为克服酯交换反应精馏中均相催化剂与体系难分离等缺陷,以γ-Al2O3为载体,氟化钾为活性中心,通过等体积浸渍法制备不同焙烧温度下的KF/γ-Al2O3固体碱催化剂,并利用XRD、FTIP对催化剂进行表征。通过反应精馏的方法对KF/Al2O3催化碳酸乙烯酯的酯交换合成碳酸二甲酯进行研究,考察了反应精馏过程中回流比、进料空速及原料摩尔比对碳酸乙烯酯转化率的影响。结果表明,回流比、进料空速与原料摩尔比优化值分别为5、0. 09 h^-1和5时,碳酸乙烯酯的转化率为95. 44%。

In order to overcome the defect that the separation between homogeneous catalyst and system is difficult in the transesterification reactive distillation,KF/γ-Al2O3 solid base catalysts are prepared by using γ-Al2O3 as carrier and potassium fluoride as active center under different calcination temperatures.The catalyst samples are characterized by XRD and FTIP. The transesterification reactive distillation method is used to convert ethylene carbonate into dimethyl carbonate over KF/Al2O3 samples.Effects of reflux ratio,feed space velocity and the molar ratio of raw materials on the conversion rate of ethylene carbonate in reactive distillation are studied.The results show that the optimum values of reflux ratio,feed space velocity and the molar ratio of raw materials are 5,0. 09 h^-1 and 5,respectively.Under these conditions,the conversion rate of ethylene carbonate can reach 95. 44%.