| Catalysts were prepared and used for the catalytic combustion of ethyl acetate. The influence of catalyst support and active component on the catalytic activities was studied. X-ray diffraction (XRD), X-ray photoelectron spectra(XPS),temperature programmed reduction (TPR), oxygen storage capacity(OSC) and BET surface area measurements were used to study the properties of the catalysts. The relationship between the properties and catalytic activities was developed.Alumina-supported manganese catalyst Mn/Al2O3 was prepared, and then Mn/Al2O3-Ce0.5Zr0.5O2 mixed oxide catalysts with different mass ratio of Al2O3 to Ce0.5Zr0.5O2 were prepared by adding Ce0.5Zr0.5O2 to catalyst Mn/Al2O3. These catalysts were tested in the combustion of ethyl acetate. The catalytic activities of Mn/Al2O3-Ce0.5Zr0.5O2 were better than catalyst Mn/Al2O3. Catalyst Mn/Al2O3-Ce0.5Zr0.5O2 (1:2,mass ratio of Al2O3 to Ce0.5Zr0.5O2 is 1:2) was the most active and more than 98% conversion of ethyl acetate (37182ppm) was achieved at 250℃, while for Mn/Al2O3, Mn/Al2O3-Ce0.5Zr0.5O2 (1:1) and Mn/Al2O3-Ce0.5Zr0.5O2 (2:1) , conversion of higher than 98% was achieved at 290℃, 275℃and 270℃, respectively. And 98% conversion of ethyl acetate (15636ppm) was reached at 200℃on catalyst Mn/Al2O3-Ce0.5Zr0.5O2 (1:2), while at 260℃, 230℃and 220℃on catalysts Mn/Al2O3,Mn/Al2O3-Ce0.5Zr0.5O2(2:1)and Mn/Al2O3-Ce0.5Zr0.5O2(1:1), respectively.From XRD results, it could be seen that Mn existed in the form of MnO2 and Mn2O3. With increasing amount of Ce0.5Zr0.5O2, the surface area and pore volume of the catalyst Mn/Al2O3 decreased, while the oxygen storage amount increased. TPR result showed that interaction between Al2O3 and Ce0.5Zr0.5O2 occurred. On the basis of characterization data, it has been suggested that the adding of Ce0.5Zr0.5O2 in catalyst Mn/Al2O3 greatly changed its textural and oxygen storage properties. The high activity of catalyst Mn/Al2O3-Ce0.5Zr0.5O2 (1:2) was due to its high OSC instead of its surface area.Manganese loading of catalyst Mn/Al2O3-Ce0.5Zr0.5O2 (1:2) was changed, the influence of active component loading on the catalytic activities was studied. 10.0%(wt%) Mn/Al2O3-Ce0.5Zr0.5O2 (1:2) has the highest activity.Fe, Co, Cu, Cr, Mn metal oxide catalysts using Al2O3-Ce0.5Zr0.5O2 mixed oxide as support were prepared and tested in the combustion of ethyl acetate (24343ppm). Cu/Al2O3-Ce0.5Zr0.5O2 (1:2) and Mn/Al2O3-Ce0.5Zr0.5O2 (1:2) catalysts were the most active for the catalytic combustion of ethyl acetate. More than 99% conversion was achieved at 245℃on both Cu/Al2O3-Ce0.5Zr0.5O2 (1:2) and Mn/Al2O3-Ce0.5Zr0.5O2(1:2) catalysts, while for Fe/Al2O3-Ce0.5Zr0.5O2 (1:2) and Cr/Al2O3-Ce0.5Zr0.5O2(1:2) catalysts a temperature of 265℃was needed, and for Co/Al2O3-Ce0.5Zr0.5O2(1:2)catalyst a higher temperature of 270℃was needed. From XRD result, it could be seen that Co,Cu and Cr existed in the form of Co3O4, CuO和Cr2O3. From the XPS and TPR results, it could be known that Fe existed in the form of Fe2O3。From the TPR result,the reduction of catalysts Cu/Al2O3-Ce0.5Zr0.5O2 (1:2) and Mn/Al2O3-Ce0.5Zr0.5O2 (1:2) began at very low temperatures and their reduction peak areas were very large。It had been suggested that the high catalytic activities of catalysts Cu/Al2O3-Ce0.5Zr0.5O2 (1:2) and Mn/Al2O3-Ce0.5Zr0.5O2(1:2) were related with the high reducibility,the high oxygen storage velocity and the existence of partially oxidized copper and Manganese phase.Bimetal catalysts Mn-X/Al2O3-Ce0.5Zr0.5O2 (1:2) (X=Fe, Co, Cu) were prepared using separate-dipping and co-dipping methods, respectively. The amount of Mn was kept 10%(wt%), the amount of Fe/Co/Cu was changed. The influence of catalyst preparation method and active component loading on the catalyst activities was studied. It was found that dipping ways of catalysts and adding amount of Fe/Co/Cu had great influence on the textural properties, oxygen storage capacities and catalytic activities.
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