离子液体催化苯与环己烯的烷基化合成环己基苯

Synthesis of Cyclohexylbenzene by Alkylation of Benzene with Cyclohexene Catalyzed by Ionic Liquid

为了提高苯和环己烯烷基化反应的收率,先考察了不同离子液体对反应的影响,确定以盐酸三乙胺与ZnC l2形成的离子液体为催化剂活性最高,然后考察了它的用量、苯和环己烯的摩尔比、反应时间、原料中的水含量等因素对苯与环己烯烷基化反应的影响。实验结果表明,离子液体的催化活性与其酸强度密切相关,只有在酸性条件下离子液体对苯与环己烯的烷基化反应才有催化活性。在催化剂用量x(离子液体)=4%,n(苯)/n(环己烯)=15、反应温度为80℃及常压反应条件下,环己烯的转化率达100%,环己基苯的选择性可达到89.63%。离子液体催化剂可重复使用,活性基本没有降低。

Ionic liquid prepared by triethylamine hydrochloride and anhydrous ZnCl2 was selected as catalyst from a series of ionic liquids for the alkylation of benzene with cyclohexene. The results show that only the acidic ionic liquid has good catalytic activity, and the activity of ionic liquid correlated strongly with its acidity. With benzene and cyclohexene in molar ratio 15：1 and 4 mol% ionic liquid at 80 ℃ and under atmospheric pressure, 100 % conversion of cyclohexene and 89. 63% selectivity to cyclohexylbenzene were achieved. The ionic liquid could be reused,and showed almost no decrease in activity.