The Preparation For Supported Nobel Catalyst Used For Ethanol Synthesis And Propane Dehydrogenation Reaction

Precious metal catalysts have attracted much attention because of their excellent activity and selectivity for the hydrogenation reaction and the dehydrogenation reaction.The reaserch on precious metal catalyst has not made much progress due to costly and the atomic utilization is not high.Aiming at the problem of atomic utilization rate and the stability in the noble catalyst prepared by conventional impregnation method,in my present,we have proposed to prepare the Rh-x%Mn/CF and La Pt_xIn_1-xO₃/Al₂O₃ catalysts by citric acid complexation used for ethanol synthesis and propane dehydrogenation reaction,respectively.We have investigated the effects of different preparation methods and further studied different amount of additives added on the reaction.A series of Rh-x%Mn/CF and Rh-2%Mn/CF-A catalysts were successfully prepared by citric acid complexation method and conventional impregnation method used for ethanol synthesis from syngas.The structure and physico-chemical properties of samples have been characterized by TPR,XRD,TEM-EDS,CO-TPD,H₂chemisorption,and XPS techniques and the catalytic performance for ethanol synthesis from syngas has been evaluated.The results show that the new method is beneficial to forming close contact Rh-Mn species than that of the conventional impregnation method.This can enhance the dispersion and sintering resistance of Rh and effectively improve activity of the CO hydrogenation and the selectivity to ethanol in ethanol synthesis from syngas.In addition,appropriate amount of Mn added can not only improve the CO conversion but also can improve the selectivity of ethanol in comparison with Rh/CF and Rh-x%Mn/CF.In addition,a series of supported Pt-based catalysts with perovskite as precursors were prepared by citric acid complexation method and used for propane dehydrogenation reaction.The effect of preparation method and different support?Al₂O₃,TiO₂,SiO₂?in propane dehydrogenation reaction were investigated.The results indicated that Al₂O₃ supported perovskite catalyst exhibits a good propane conversion and the selectivity of propylene compared with TiO₂ and SiO₂ as support.On the basis of this study,a series of 20%LaPtxIn1-x O3/Al2O3 catalyst with different Pt loading?0.5%-1.5wt%?were researched.Propane conversion reached 26%and the selectivity of propylene was 95%of when the loading of Pt is 1.5%under the experiments condition of 600°C.The catalyst of perovskite as precursors exhibits excellent stability compared with the catalyst prepared by conventional impregnation method.