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A series of novel Ni/CeO2-Al2O3composite catalysts were synthesized by one-step citric acid complex method. The as-synthesized catalysts were characterized by N2physical adsorption/desorption, X-ray diffraction(XRD), Fourier transform infrared(FT-IR) spectroscopy, hydrogen temperature-programmed reduction(H2-TPR), X-ray photoelectron spectroscopy(XPS) and thermogravimetry analysis(TGA). The effects of nickel content, calcination and reaction temperatures, gas hourly space velocity(GHSV) and inert gas dilution of N2on their performance of catalytic partial oxidation of methane(CPOM) were investigated. Catalytic activity test results show that the highest methane conversion(>85%), the best selectivities to carbon monoxide(>87%) and to hydrogen(>95%), the excellent stability and perfect H2/CO ratio(2.0) can be obtained over Ni/CeO2-Al2O3with 8 wt% Ni content calcined at 700 ℃ under the reaction condition of 750 ℃, CH4/O2ratio of 2 : 1 and gas hourly space velocity of 12000 mL h-1 g-1. Characterization results show that the good catalytic performance of this composite catalyst can be contributed to its large specific surface area(～108 m2 g-1), small crystallite size, easy reducibility and low coking rate.
A series of novel Ni / CeO2-Al2O3composite catalysts were synthesized by one-step citric acid complex method. The as-synthesized catalysts were characterized by N2physical adsorption / desorption, X-ray diffraction (XRD) spectroscopy, hydrogen temperature-programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS) and thermogravimetry analysis (TGA). The effects of nickel content, calcination and reaction temperatures, gas hourly space velocity (GHSV) Catalytic activity test results show that the highest methane conversion (> 85%), the best selectivities to carbon monoxide (> 87%) and to hydrogen (> 95% ), the excellent stability and perfect H2 / CO ratio (2.0) can be obtained over Ni / CeO2-Al2O3 with 8 wt% Ni content calcined at 700 ° C. under the reaction condition of 750 ° C., CH4 / O2 ratio of 2: space velocity of 12000 mL h-1 g-1. Characterization results show that the good catalytic performance of this composite catalyst can be contributed to its large specific surface area (~ 108 m2 g-1), small crystallite size, easy reducibility and low coking rate.