介孔分子筛SiW_(12)/SBA-15催化合成柠檬酸三丁酯

Synthesis of tributyl citrate over mesoporous molecular sieve SiW_(12)/SBA-15

将硅钨酸负载在纯硅介孔分子筛SBA-15的表面上,XRD结果表明负载型催化剂SiW_(12)/ SBA-15具有纯硅SBA-15的介孔结构。将该催化剂用于合成柠檬酸三丁酯的酯化反应。采用正交实验考察了反应温度、催化剂用量、酸醇摩尔比对柠檬酸转化率的影响,得出最佳反应条件为:反应温度120℃、催化剂用量为总物料质量的1.5%、酸醇摩尔比1:4。在此条件下反应4 h,柠檬酸转化率可达到91.5%,产物的纯度为99.3%。

The mesoporous molecular sieve SiW12/SBA-15 functionlized with silicotungstic acid was prepared. The XRD results showed that the structure of SiW12/SBA-15 catalyst remains that of silica mesoporous molecular sieve SBA-15. The synthesis of tributyl citrate from citric acid and butanol was carried over catalyst SiW12/SBA-15. The influences of reaction temperature,ratio of citric acid to butanol,and the mass of catalyst on esterification performance were emphatically studied. The optimal reaction conditions have been obtained by orthogonal design test：temperature, 120℃ ;mass ratio of catalyst to reactant,1.5% the ratio of citric acid to butanol, 1 ： 4. The conversion of citric acid is 91.5% under optimal reaction condition,and the purity of the product is 99.3%.