用环境友好催化剂催化合成氯乙酸酯的研究

报道了以TiSiW12O40/TiO2为催化剂，对以乙醇、丙醇、丁醇、戊醇和氯乙酸为原料合成氯乙酸系列酯的反应条件进行了研究。实验表明，TiSiW12O40/TiO2是合成氯乙酸系列酯的良好催化剂。最佳反应条件为：n(醇）：n(酸）为1．4：1，催化剂用量为反应物料总质量的2．0％，反应时间2h。上述条件下，氯乙酸乙酯的收率为49．84％，氯乙酸丙酯的收率为69．98％，氯乙酸丁酯的收率为92．78％，氯乙酸异戊酯的收率为93．33％。

Study of the Catalytic Synthesis of Chloroacetates wit h TiSiW12O40/TiO2

Chloroacetates were synthesized in high yield by the esterification of ethyl alcohol, propyl alcohol, n -butyl alcohol, n - amyl alcohol with chloroacetic acid in the presence of a new environmentally friendly catalyst, TiSiW12O40/TiO2. The results obtained indicated that TiSiW12O40/TiO2 possessed a fairly high catalytic activity for the esterification reaction. The factors influencing the synthesis were discussed and the best conditions were determined . The optimum conditions were as follows: the molar ratio of alcohol to acid was 1.4:1, the mass ratio of the catalyst used to the reactants was 2.0% , and the reaction time was 2.0 h. Under this conditions, the yield of ethyl chloroacetate 49.84% , propyl chloroacetate 69.98% , n - butyl chloroacetate 92.78% , isoamyl chloroacetate 93 . 33% .The catalytic activities of TiSiW12O40/TiO2 were almost unchanged after it had been used five times. The results showed that TiSiW12O40/TiO2 was an excellant catalyst for synthetizing chloroacetates.