无机盐在HZSM-5催化乙酸环己酯水解反应中的作用  

The Role of Inorganic Salts in Hydrolyzation of Cyclohexyl Acetate Over HZSM-5

作　　者：提飞 李芳[1] 王志苗[1] 张东升[1] 薛伟[1] 王延吉[1] 

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

出　　处：《石油学报（石油加工）》2017年第1期85-90,共6页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(21236001;21176056);河北省自然科学基金项目(B2015202228);河北省高校百名优秀创新人才项目(BR2-208)资助

摘　　要：考察了无机盐(NaBr、ZnSO_4、NaHSO_4)对HZSM-5催化乙酸环己酯水解制备环己醇反应的影响。结果表明,无机盐可以增加反应体系的极性,抑制乙酸环己酯热分解副反应(β-消除反应)过渡态的生成,从而提高环己醇的选择性。同时,无机盐会破坏HZSM-5表面B酸中心,降低其催化活性。单独使用NaHSO_4对乙酸环己酯水解反应也具有较好的催化性能,在适宜条件下,乙酸环己酯转化率达到63.8%,环己醇选择性达到90.9%;重复使用时,由于乙酸在反应体系中的积累,乙酸环己酯转化率有所降低,环己醇选择性基本不变。Effect of inorganic salts（such as NaBr,ZnSO_4 and NaHSO_4）on catalytic hydrolyzation of cyclohexyl acetate to cyclohexanol over HZSM-5catalyst was studied.It is found that the inorganic salts could prohibit the formation of the transition state for the side reaction（pyrolysis of cyclohexyl acetate to cyclohexene,aβ-elimination reaction）by increasing the polarity of the reaction system,and thus high cyclohexanol selectivity was obtained.At the same time,inorganic salts destroyed the acid sites of Brnsted type on the surface of HZSM-5,resulting in the decrease of its catalytic activity.NaHSO_4 also showed good catalytic performance when it was employed as catalyst alone in this reaction,with cyclohexyl acetate of 63.8% and cyclohexanol selectivity of 90.9%under the certain conditions.When NaHSO_4 was recycle used,cyclohexanol selectivity changed little,while cyclohexyl acetate conversion decreased with recycle times increasing,which could be attributed to the accumulation of acetic acid in the reaction system.

关 键 词：环己醇 乙酸环己酯 水解 环己烯 硫酸氢钠 

分 类 号：O643.3[理学—物理化学] TQ233.1[理学—化学]