由苯“一锅法”制备环己醇催化反应研究——ZnSO_4对HZSM-5催化环己烯水合反应的影响  

Study on the One-pot Catalytic Synthesis of Cyclohexanol from Benzene ——Influence of ZnSO_4 on the Hydration of Cyclohexene Catalyzed by HZSM-5

作　　者：薛伟[1] 王冬冬[1] 李芳[1] 魏珺芳[1] 王延吉[1] 

机构地区：[1]河北工业大学绿色化工与高效节能河北省重点实验室,天津300130

出　　处：《高校化学工程学报》2011年第6期1026-1032,共7页Journal of Chemical Engineering of Chinese Universities

基　　金：973计划前期研究专项(2010CB234602);国家自然科学基金资助项目(20706011;20876033;21176056);河北省自然科学基金资助项目(B2010000023)

摘　　要：对由苯"一锅法"制备环己醇催化反应过程进行了研究,考察了苯选择加氢反应体系中各物质对环己烯水合反应的影响。发现用于提高环己烯选择性的ZnSO4助剂对环己烯水合反应存在显著的负作用,当ZnSO4浓度为0.2 mol·L-1时,环己醇收率仅为1.0%。对环己烯水合反应用催化剂HZSM-5进行了表征,认为ZnSO4导致了HZSM-5的部分脱铝,减少了其表面Al-OH数量,亦即减少了表面B酸中心数量,从而使其催化环己烯水合反应的活性下降。对ZnSO4的替代物进行了考察,发现Al2(SO4)3对HZSM-5的影响较小,当其浓度为0.2 mol·L-1时,环己醇收率为7.0%。Al2(SO4)3可在"一锅法"制备环己醇反应中作为提高苯选择加氢制环己烯选择性的助剂。One-pot catalytic synthesis of cyclohexanol from benzene was studied,and the influence of compounds involved in benzene selective hydrogenation on the hydration of cyclohexene was investigated.It was found that the ZnSO4 which was used as promoter for increasing cyclohexene selectivity shows great negative impact on the cyclohexene hydration.When ZnSO4 concentration in water is 0.2 mol·L-1,the cyclohexanol yield is only 1.0%.NH3-TPD,Py-IR,FT-IR and XRD were used respectively to investigate the change of HZSM-5,the catalyst for cyclohexene hydration.It could be concluded that the ZnSO4 leads to the dealuminization of HZSM-5 during reaction,which results in the decrease of Al-OH on the surface of HZSM-5.In other words,the amount of Br·nsted acid sites on HZSM-5 decreases,thereby its catalytic performance for cyclohexene hydration decreases.The substitution for ZnSO4 was explored,and it was found that the Al2（SO4）3 shows relatively weak effect on HZSM-5.When Al2（SO4）3 concentration is 0.2 mol·L-1,the cyclohexanol yield is 7.0%.Therefore Al2（SO4）3 can be used as the promoter for benzene selective hydrogenation in the one-pot synthesis of cyclohexanol from benzene.

关 键 词：环己醇 一锅法 HZSM-5 ZnSO4 脱铝 

分 类 号：O643.32[理学—物理化学]