| The states of energy sources is"a coal-rich, short of petroleum"in the China. Along with economic development, environmental pollution will be more and more serious. Therefore, the searching for less polluting alternative energy sources becomes a priority. DME production technology has been maturity, and then yield increases significant. Now dimethyl ether with low pollution and good combustion properties, is a good selection of alternative energy sources. DME will be widely used in the civilian areas of fuel and vehicle fuel.In this thesis, the catalytic performances of Cu-Ce/γ-Al2O3,3%Cu-Ce-La/γ-Al2O3,3% Zr1-xCuxO2-x/γ-Al2O3,Zr1-xCuxO2,5%Cu-Ce carried mesoporousγ-Al2O3 catalysts for the combustion of DME with air were studied. The results are summarized as follows:1. The main catalyst of Cu-Ce/γ-Al2O3 catalyst for catalytic combustion of dimethyl ether was the Ce and Cu solid solution, and solid solution improved catalytic performance. The oxidation productions of dimethyl ether were without carbon monoxide.2. Ce0.1Cu0.9O1.1/γ-Al2O3 catalysts with different loadings were performed to investigate the catalytic combustion of dimethyl ether shows: loading less than 6%, the active component and solid solution dispersed well on theγ-Al2O3, and the catalytic effect is good. When the excessive loading, the catalytic activity made no changes, or even lower, because the effect of active components on theγ-Al2O3 dispersed. And varies loadings of catalyst, dimethyl ether oxidation products were not carbon monoxide.3. La doping can improve the performance of the Ce0.1Cu0.9O1.1/γ-Al2O3 catalyst, but when excessive doped catalysts, the catalytic activity reduced. Among them, La0.4-Ce0.1Cu0.9O1.1 /γ-Al2O3 catalyst of the catalytic combustion of dimethyl ether was the best performance, and the combustion temperature (DME conversion reached 10% of the temperature, denoted by T10) was 235℃, complete conversion temperature (the conversion of dimethyl ether 90% of the temperature, denoted T90) for the 244.8℃. But when the temperature reached the ignition temperature, there were carbon monoxide, so dimethyl ether oxidation was incomplete.4. Mesoporous materialsγ-Al2O3 preparated by organic small molecule as a template and aluminum nitrate as the aluminum source. Among them, glucose as the template preparedγ-Al2O3 has larger surface area and pore volume, pore size distribution and crystal shape better. And as the carrier prepared by catalyst, the catalyst studied on the catalytic combustion of dimethyl ether. Results showed that: thisγ-Al2O3-glu could promote the catalyst performance.5. Catalytic activity of 5% La0.4-Ce0.1Cu0.9O1.1/γ-Al2O3-glu catalyst was better than the other catalysts. Its T10 was 220℃, and T90 was 224℃, the production had a small amount of carbon monoxide. The life time of catalyst was investigated, and the result indicated that the catalyst activity had not any reduce after 100h reaction.6. Among the co-precipitation of Zr1-xCuxO2 catalysts, ignition temperature of Zr0.4Cu0.6O2 catalyst was the lowest, that is, T10 =261.5℃. And Zr0.1u0.9O2 and Zr0.2Cu0.8O2 catalysts exhibited the lowest complete conversion temperature , that is, T90= 279℃. Among the sol-gel of method Zr1-xCuxO2 catalysts, Zr0.3Cu0.7O2 catalyst was the best catalyst for the catalytic combustion of dimethyl ether. Its T10 was 255℃and T90 was 259.7℃. Among the 3% Zr0.1Cu0.9O1.1 /γ-Al2O3 catalyst by impregnation method, 3%Zr1-xCuxO2-x /γ-Al2O3(x=0~0.9) catalyst exhibited the best catalytic performance for DME combustion, and T10 was 217.8℃, T90 was 244.7℃Zr doping made the DME catalytic combustion incompletely, and there were more by-products, especially carbon monoxide was higher.7. Perovskite catalyst of LaMnO3, CaMnO3 and BaMnO3 catalysts had better performance for catalytic combustion of dimethyl ether, in which LaMn03 was the best one, and T10 was 215.3℃, and T90 was 219.9℃, but the catalyst was less stable.
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