盐酸三乙胺-三氯化铝离子液体催化甲苯与氯代叔丁烷烷基化反应

摘要

用盐酸三乙胺和无水三氯化铝合成了不同配比的Et 3NHCl-AlCl3离子液体,研究了反应时间、反应温度、离子液体的用量、甲苯与氯代叔丁烷摩尔比对烷基化反应的影响.结果表明,Et 3NHCl-AlCl3酸性离子液体具有较高的催化活性,良好的低温反应活性和对位选择性.得到了该反应优化反应条件：离子液体中AlCl3与Et 3NHCl的摩尔比1.6,反应温度20℃,离子液体的用量为甲苯质量的10%,甲苯与氯代叔丁烷摩尔比2,反应10 min.该条件下,氯代叔丁烷的转化率为98%,对叔丁基甲苯的选择性为82.5%.离子液体重复使用5次,其催化活性不变,离子液体再生后可循环使用.%Different kinds of ionic liquids were prepared with different molar ratios of AlCl3 to Et3NHCl, and the effects of the reaction time, reaction temperature, ionic liquid dosage, as well as the molar ratio of toluene to chloro-2-methylpropane on the alkylation reaction of toluene with chloro-2-methylpropane were investigated. The results show that the acidic ionic liquids prepared with Et3NHCl and AlCl3 have good activity and selectivity for the alkylation reaction of toluene with alkyl chloride to produce p-tert-butyltoluene (PTBT). The suitable reaction conditions are the ratio of AlCl3 to Et3NHCl 1.6, reaction temperature 20℃, the mass fraction of ionic liquid to toluene 10% and molar ratio of toluene to chloro-2-methylpropane 2. Under the suitable reaction condition, 98%conversion of chloro-2-methylpropane and 82.5%selectivity of PTBT can be obtained. The ionic liquids can be reused 5 times with their catalytic activity unchanged, and the regenerated ionic liquids can be recycled.