| Energy is closely related to human beings and is the basic material guarantee of social development and progress.China’s consumption of energy is increasing with the rapid development of economy.Coal energy is still the main energy source for China’s consumption and occupies a dominant position based on China’s energy consumption structure.However,the unreasonable use of coal resources has brought great environmental problems to our country.As a green,clean and renewable resource,natural gas has attracted widespread attention.The demand for natural gas in China is also increasing.However,according to relevant statistics,China’s natural gas reserves are small,most of the natural gas required for energy consumption depends on imports,and the dependence on natural gas is increasing,which is detrimental to China’s economic development and the rational use of energy.Therefore,it is important to find new sources of natural gas.As a renewable energy source,biomass can be converted into the fuel through physical or chemical methods.They can be transformed into Bio-fuels what we need by certain methods.There are a lot of reports about the method of producing methane by anaerobic digestion of biomass abroad.Nowadays,more applications for biogas are to ferment to generate biogas,which is used as fuel.However,the biogas formed by this method contains CO,CO2 and other gases,the content of methane and the calorific value of combustion is not high enough,as well as the gas composition does not meet the national standards.Therefore,how to increase the content of methane and reduce the content of other gases is a problem to be solved.In this paper,γ-Al2O3/cordierite was prepared using sol-gel method through the research of cordierite honeycomb ceramic coating method.A series of Ni catalysts with different Ni contents were prepared by impregnation.The structure of the catalyst was characterized by XRD,SEM,BET,H2-TPR,TG and XPS.We investigated the influence of coating rate of γ-Al2O3,the content of Ni,the calcination temperature,the reduction temperature the space velocity on methanation reaction.The results show that the optimal coating rate of γ-Al2O3 on the surface of honeycomb ceramics is 20%,and the optimum loading of Ni is 30%.At a space velocity of 10000 h-1,the reaction temperature of 400 °C and reaction feed gas V(H2): V(CO): V(N2)=0.45: 0.15: 0.4,the CO conversion rate reaches 100%,and the yield of CH4 reaches 89%.In the range of 370 °C-450 °C,the yield of CH4 is greater than 86%.The above catalysts were tested for a 40 h life test under the reaction temperature of 400 °C,the results showed that the catalyst in the reaction within the first 15 h,the yield of methane is between 86% and 88%,within the next 25 h,the yield also remains above 82%.In addition,we have also applied the catalyst to the reaction under conditions of different ratio of V(H2): V(CO)for feed gas.In the experiment,the catalysts were also used under different conditions of feed gas with H2 and CO.Compared with the powder catalysts,the catalysts show better catalytic effects and has a certain application prospects in the large-scale industrial application of the catalyst. |
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