硅酸钠催化制备碳酸甘油酯

Catalytic synthesis of glycerol carbonate via sodium silicate

针对催化制备碳酸甘油酯过程中催化剂易失活、难回收的问题,以Na2Si O3·9H2O为原料,经焙烧、研磨、过筛等工艺处理后,制备得到了易分离且可循环使用的固体碱催化剂,并用于催化甘油与碳酸二甲酯的酯交换反应.探讨了催化剂的粒度和煅烧时间对催化剂活性的影响,以及甘油与碳酸二甲酯的摩尔比、催化剂用量、反应时间等反应条件对酯交换反应的影响.结果表明,当催化剂用量为反应物质量的5%且甘油与碳酸二甲酯的摩尔比为1∶4时,在75℃反应2.5 h后甘油转化率高达97.8%,碳酸甘油酯收率为95.5%.

Aiming at the easy loss and difficult recovery of catalyst in the catalytic synthesis of glycerol carbonate（ GC）,the solid base catalyst with easier separation and better reusability was prepared through taking Na2 Si O3·9 H2 O as the rawmaterial and with such processes as calcination,grinding and sieving,and was used for the catalysis of transterification reaction between glycerol and dimethyl carbonate（ DMC）. The effect of granularity and calcination time of catalyst on the catalyst activity was investigated,and the influence of such reaction conditions as the mole ratio of glycerol to DMC,catalyst dosage and reaction time on the transesterification reaction was determined. The results showthat when the catalyst dosage is as 5%as the mass of reagents and the molar ratio is 1（ glycerol） ∶ 4（ DMC）,the glycerol conversion rate can reach as high as 97. 8%,and the GC yield is 95. 5% after the reaction for 2. 5 h at 75 ℃.