难溶杂多酸盐催化合成对羟基苯甲酸酯的研究

Preparation of p-Hydroxybenzoic Acid Ester with Insoluble Salt of Heteropoly-acid as Catalyst

以钨硅酸和三乙醇胺为原料首先合成了钨硅酸三乙醇胺盐 ,并首次用于对羟基苯甲酸酯的催化合成研究。实验考察了催化剂用量、醇酸的量比、反应时间对酯收率的影响。结果表明 ,该催化剂具有较高的催化活性 ,酯收率达到 91.6 % ,且不溶于醇 ,易于回收 ,可重复使用

Triethanolamine salt of tungstosilicic acid was prepared from tungstosilicic acid and triethanolamine,and was used in the preparation of p hydroxybenzoic acid ester as catalyst for the first time.The influences of such factors as the amount of the catalyst,the mole ratio of alcohol to acid and reacton time on the yield of ester were investigated.The results showed that the salt of heteropoly acid had rather high catalytic activity,the yield of the ester reached 91.6%,and the catalyst is insoluble in alcohol and can be recovered and reused for more than five times.