Catalytic Performance Of Pt-Ga And Ga-Mo Bimetallic Catalysts In Propane Dehydrogenation

In propane dehydrogenation,the deactivation of Pt catalysts as well as their high cost has an important influence on their economics and technical feasibility.Therefore,development of catalysts with high catalytic performance and low cost is still an important issue in this process.In this work,Pt-Ga bimetallic catalysts with different Ga loadings are prepared by incipient wetness impregnation.The structure and coking properties are studied by CO chemisorption,XRD,CO-FTIR,Raman,TEM,and other characterization methods.The effect of Ga on Pt-Ga catalysts is examined,the catalytic performance of which is compared with that of Pt-Sn catalysts.Experimental results show that the introduction of Ga can improve the catalytic performance of the catalysts.The PtGa2 catalyst has better performance than PtSn under the same loading and reaction conditions.The optimal Ga loading is 0.2 wt%,giving rise to the lowest coking rate,which is mainly ascribed to the synergetic effect of Ga on Pt.In addition,considering the good dehydrogenation performance of gallium-based catalysts,Ga-Mo bimetallic catalysts are also prepared and their catalytic performance is investigated in propane dehydrogenation.The effects of support,calcination temperature,reduction temperature,and partial pressure of H2 on the catalytic activity and selectivity of the Ga3Mo catalyst in propane dehydrogenation are explored.It is found that the addition of Mo can partially block Ga active sites,causing the decrease of catalyst activity,but the addition of Mo can inhibit the formation of graphite-like carbon on the catalyst.The results regarding the modification of Pt-based catalysts and the development of non-precious metal catalysts could guide the investigation toward better catalysts in propane dehydrogenation.