Study On Catalytic Materials For Dry Reforming Of Mathane

Dry reforming of methane(DRM),as a indirect way of methane conversion, is focused by researchers recently because of its alternating meanings of environmental protection?solving the energy problem and comprehensive utilization of resources. Meanwhile, Ni-Co bimetallic catalysts have attracted much attention because of its advantages of the adjustable electronic and geoetric structure?the synergistic effect and the formation of alloy. This essay is aimed to promote the resistance of carbon deposition providing that the catalysts keep its activity. We studied the catalysts for DRM by comparing the single metal catalysts and bimetallic catalysts ? rationally adding promoters and controlling the content of the components as well as improving preparation method.The Ni-Co bimetallic catalysts were prepared by two-step hydrothermal method, and the properties of the bimetallic catalysts were studied. The bimetallic catalyst prepared by two-step hydrothermal method has a reactivity of up to 91.14%. The results show that the bimetallic catalyst has a larger specific surface area and provides good adsorption and activation of methane and carbon dioxide. The addition of Co has a certain guiding effect to the growth of the catalyst. Through the H2-TPR characterization, it is found that the reduction peak of Ni-Co bimetallic catalyst Moving to the low temperature region and showing a more suitable proportion of different forms of nickel,and thus have better reduction properties; by TG analysis, the catalyst prepared by two-step hydrothennal method shows a more serious deposition of carbon. The results showed that the optimum additive loading of bimetallic catalyst prepared by two-step hydrothermal method was 10%, and it was found that the promoters such as La2O3, CeO2 and CaO could be an ideal additive to improve the performance of the catalyst, and the activity and stability of the catalyst modified by K20 and MgO are poor. The two oxides are not suitable as the additives of the catalyst.In order to further improve the carbon deposition resistance of the catalyst, the preparation method of the catalyst was improved and the catalyst was prepared by modified hydrothermal-impregnation method. Activity evaluation and TG analysis showed that the catalyst prepared by the two method had similar activity, but the catalyst prepared by improved hydrothermal-impregnation method had better resistance of carbon deposition which is 36% lower than that of the catalyst prepared by two-step hydrothermal method. The catalyst prepared by improved hydrothermal impregnation method has a large surface area of 223.367m2 / g, which is 53%higher than that prepared by two-step hydrothermal method. Finally, the loading forms and loading of different active components are compared. The results of BET, TPR and TG show that nickel nitrate is more suitable for loading than nickel hydroxide, and the optimum active components load is 10%.