[BMIm]Br离子液体辅助HZSM-5催化乙酸环己酯高选择性水解反应  

Highly selective hydrolyzation of cyclohexyl acetate over HZSM-5 assisted by[BMIm]Br ionic liquid

作　　者：朱林 韩威 李文松 邬长城 李芳[1,2] 薛伟 王延吉[1,2] ZHU Lin;HAN Wei;LI Wensong;WU Changcheng;LI Fang;XUE Wei;WANG Yanji(Hebei Provincial Key Laboratory of Green Chemical Technology and High Efficient Energy Saving,School of Chemical Engineering and Technology,Hebei University of Technology,Tianjin 300130,China;Tianjin Key Laboratory of Chemical Process Safety,Tianjin 300130,China)

机构地区：[1]河北工业大学化工学院,河北省绿色化工与高效节能重点实验室,天津300130 [2]天津市本质安全化工技术重点实验室,天津300130

出　　处：《化工学报》2020年第4期1609-1617,共9页CIESC Journal

基　　金：国家自然科学基金项目(21776057);天津市自然科学基金项目(17JCYBJC20100,18JCYBJC21500);河北省留学人员科技活动择优资助项目(CL201605)。

摘　　要：为提高HZSM-5催化乙酸环己酯水解反应生成环己醇的选择性,筛选得到了离子液体[BMIm]Br助剂。发现[BMIm]Br可抑制乙酸环己酯热分解副反应的发生,大幅度提高环己醇选择性。并且,[BMIm]Br可与HZSM-5发生离子交换反应,释放出的H+可促进乙酸环己酯水解反应的发生。在优化的条件下,[BMIm]Br辅助HZSM-5催化乙酸环己酯水解反应转化率为87.5%,环己醇选择性为97.3%。考察了[BMIm]Br和HZSM-5的重复使用性。前者具有较好的稳定性,而HZSM-5活性随循环使用的次数增加而下降。这是由于HZSM-5的骨架铝含量在反应中逐渐降低,导致Br nsted酸中心数量减少,因此其催化活性逐渐降低。To improve the selectivity of HZSM-5 to catalyze the hydrolysis reaction of cyclohexyl acetate to cyclohexanol,an ionic liquid[BMIm]Br auxiliary was screened.It was found that[BMIm]Br could inhibit the sidereaction,thermal decomposition of cyclohexyl acetate,and increase the selectivity to cyclohexanol greatly.Moreover,the ion exchange between[BMIm]Br and HZSM-5 could promote the generation of H+,which could accelerate the hydrolyzation of cyclohexyl acetate.Under the optimized reaction conditions,cyclohexyl acetate conversion was 87.5%with 97.3%cyclohexanol selectivity over HZSM-5 assisted by[BMIm]Br.The reusability of[BMIm]Br and HZSM-5 was investigated respectively,and the former exhibited good stability.However,the catalytic activity of HZSM-5 decreased gradually with the recycling times.It was due to the decreasing of framework Al content of HZSM-5 during the reaction,which led to the reduction of Bronsted acid sites and therefore resulted in the decreased activity.

关 键 词：环己醇 乙酸环己酯 水解 HZSM-5 离子液体 

分 类 号：O643.3[理学—物理化学]