The nano ZrO2-supported copper-based catalysts for methane combustion were investigated by means of N2 adsorption, TEM, XRD, H2-TPR techniques and the test of methane oxidation. Two kinds of ZrO2 were used as support, one （ZrO2-1） was obtained from the commercial ZrO2 and the other （ZrO2-2） was issued from the thermal decomposition of zirconium nitrate. It was found that the CuO/ZrO2-2 catalyst was more active than CuO/ZrO2-1. N2 adsorption, H2-TPR and XRD measurements showed that larger surface area, better reduction property, presence of tetragonal ZrO2 and higher dispersion of active component for CuO/ZrO2-2 than that of CuO/ZrO2-1. These factors could be the dominating reasons for its higher activity for methane combustion.
The new Cu-Co based （Cu/Co/Zn/Zr） catalysts for higher-alcohol synthesis were prepared using coprecipitation method, plasma enhanced method and reverse coprecipitation method under ultrasound irradiation. The catalysts were investigated by the means of BET, SEM, XRD, H2-TPR and XPS. Catalytic properties of the catalysts prepared by various methods were examined using CO hydrogenation reaction. It was found that plasma enhanced method and reverse coprecipitation method under ultrasound irradiation were both effective in enhancing the catalytic properties of Cu/Co/Zn/Zr mixed oxides. The small particle size, high dispersion of active components, the improvement of specific surface area and surface contents of active phases could account for the excellent performance of the experimental Cu/Co/Zn/Zr catalysts.
MnOx-CeO2 mixed oxide catalysts for methane combustion were prepared with co-precipitation me-thod.With the same content of Mn,the modified catalysts were gained via adding KMnO4.These catalysts were characterized with XRD,LRS,XPS and TPR techniques,respectively.It was found that the solid solution structures of the catalysts were reserved,while the low-temperature activities were promoted remarkably duo to more Mn4+ species and easier reductions through properly changing the adding amounts of Mn(NO3)2 and KMnO4.With a molar ratio of 1:4,the MnOx-CeO2 catalyst exhibited the highest activity,over which methane conversion reached 90% at a temperature as low as 390 ℃,and a better stability.
