Enhancing the selective hydrogenation of benzene to cyclohexene over Ru/TiO_2 catalyst in the presence of a very small amount of ZnO  

作　　者：Tianbin Wu Peng Zhang Tao Jiang Dexin Yang Buxing Han 

机构地区：[1]Beijing National Laboratory for Molecular Sciences, Centre for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences

出　　处：《Science China Chemistry》2015年第1期93-100,共8页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21373230,20932002,21273253);the National Basic Research Program of China(2011CB808603);the Chinese Academy of Sciences(KJCX2.YW.H30)

摘　　要：Highly efficient and greener hydrogenation of benzene to cyclohexene is of great importance but is challenging.In this work,Ru/Ti O2 catalyst was prepared by a simple chemical-reduction method.The catalyst was characterized by transmission electron spectroscopy(TEM),X-ray powder diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and nitrogen adsorption-desorption techniques.It was shown that the Ru nanoparticles with average size of about 2.2 nm were dispersed uniformly on the surface of the Ti O2 support.The effect of a very small amount of Zn O in Na OH solution on the selectivity to cyclohexene was investigated under different conditions by using Ru/Ti O2 catalyst.It was found that the addition of a small amount of Zn O to the Na OH solution could effectively enhance the selectivity to cyclohexene and that the yield of cyclohexene could reach 41.5%.Control experiments revealed that the main reason for the enhancement of the selectivity to cyclohexene was the presence of Zn O in the form of Na2Zn(OH)4 in the alkaline solution,which effectively retarded the further hydrogenation of cyclohexene.A recycling experiment showed that the yield of cyclohexene was not obviously decreased after four reuses.Highly efficient and greener hydrogenation of benzene to cyclohexene is of great importance but is challenging. In this work, Ru/TiO2 catalyst was prepared by a simple chemical-reduction method. The catalyst was characterized by transmission electron spectroscopy （TEM）, X-ray powder diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, X-ray photoelectron spectroscopy （XPS）, and nitrogen adsorption-desorption techniques. It was shown that the Ru nanoparticles with average size of about 2.2 nm were dispersed uniformly on the surface of the TiO2 support. The effect of a very small amount of ZnO in NaOH solution on the selectivity to cyclohexene was investigated under different conditions by using Ru/TiO2 catalyst. It was found that the addition of a small amount of ZnO to the NaOH solution could effectively enhance the selectivity to cyclohexene and that the yield of cyclohexene could reach 41.5%. Control experiments revealed that the main reason for the enhancement of the selectivity to cyclohexene was the presence of ZnO in the form of Na2Zn（OH）4 in the alkaline solution, which effectively retarded the further hydrogenation of cyclohexene. A recycling experiment showed that the yield of cyclohexene was not obviously decreased after four reuses.

关 键 词：selective hydrogenation alkaline solution ZNO synergistic effect Na2Zn（OH）4 

分 类 号：O624.12[理学—有机化学] X788.03[理学—化学]