Selective hydrogenation of acetylene on SiO_2-supported Ni-Ga alloy and intermetallic compound

作     者：Lei Wang Fengxu Li Yanjun Chen Jixiang Chen Lei Wang;Fengxu Li;Yanjun Chen;Jixiang Chen

作者机构：Tianjin Key Laboratory of Applied Catalysis Science and TechnologyDepartment of Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin University 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2019年第28卷第2期

页      面：40-49页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学] 

基　　金：supported by the National Natural Science Foundation of China (21576193) 

主　　题：Selective hydrogenation Acetylene Ni-Ga alloy Ni3Ga intermetallic compound 

摘      要：Ni/Si O_2 and bimetallic Ni_xGa/SiO_2 catalysts with different Ni/Ga atomic ratios(x = 10～2) were investigated for the selective hydrogenation of *** was found that Ni_xGa/SiO_2 showed higher selectivity to ethylene than Ni/Si O_*** is attributed to the formation Ni-Ga alloy and Ni3 Ga intermetallic compound(IMC) where there was a charge transfer from Ga to Ni,which is favorable for reducing the adsorption strength and amount of ethylene on Ni *** a result,the over-hydrogenation,the C–C bond hydrogenolysis and the polymerization were suppressed,and subsequently the selectivity to ethylene was *** the decrease of Ni/Ga atomic ratio,the activity and stability of the Ni_xGa/SiO_2 catalysts increased first and then decreased,while the ethylene selectivity tended to ***_5 Ga/SiO_2 exhibited the best *** the conditions of 180 °C,0.1 MPa,and a reactant(1.0 vol% acetylene,5.0 vol% H_2 and 94 vol% N_2) with the space velocity of 36,000 m L h^(-1) g^(-1),the acetylene conversion maintained at 100% on Ni_5 Ga/SiO_2 during 120 h time on stream and the selectivity to ethylene was 75%～81%after reaction for 68 *** was also found that the formation of Ni-Ga alloy and Ni_3 Ga IMC suppressed the incorporation of carbon to form NiCx,subsequently enhancing the catalyst ***,with increasing the Ga content,the catalyst acid amount and strength tended to increase,which promoted the polymerization and carbon deposition and so the catalyst deactivation.