Zn对苯选择加氢制环己烯Ru催化剂性能的影响(英文)

Influence of Zn on Property of Ru Catalyst for Selective Hydrogenation of Benzene to Cyclohexene

采用共沉淀法制备了苯选择加氢制环己烯无负载Ru-Zn催化剂.Ru催化剂中Zn的引入,有利于降低苯的转化率和提高环己烯的选择性;Zn/Ru摩尔分数比对催化性能有明显的影响,当x(Zn)/x(Ru)=0.08时,环己烯的收率达49.1%.利用XRD和H2-TPR对其结构进行了表征,结果表明,Ru催化剂中添加Zn后,当Zn含量低时,Ru和Zn形成了固溶体;随着Zn含量的增加,Zn物种单独成相,并发现有元素态Zn的存在.

A Ru-Zn catalyst for selective hydrogenation of benzene to cyclohexene is prepared by co-precipitation of ruthenium trichloride and zinc sulfate with NaOH, followed by hydrogenation reduction in its aqueous mother liquid. The pronounced positive effect of zinc additive on the conversion of benzene and the cyclohexene selectivity and yield are investigated. Cyclohexene yield achieves 49. 1% （molar fraction） at 15 min as x（Zn）/x（Ru） ratio is 0.08. XRD and H2-TPR are also carried out to obtain better insight into the structure of the catalyst. The results show that ruthenium and zinc form a solid solution and zinc exists in its metal state in the catalyst with lower content of zinc, and while the content of zinc increases further, a new phase of zinc is found.