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The catalytic properties of electrode materials Ni/Ce1-x YxO2-δ(x=0.05,0.10,0.15 and 0.20)were investigated for partial oxidation of methane(POM).The CeO2-Y2O3 solid solutions were prepared by co-precipitaion method.The Nibased catalysts supported on the solid solutions were obtained using the impregnation method.Structural,surface and redox characteristics of the prepared catalysts were system-atically examined by means of X-ray diffraction(XRD),N2 adsorption-desorption(Brunauer-Emmet Teller BET method),H2 temperature-programmed reduction(H2-TPR)and X-ray photoelectron spectroscopy(XPS)methods.The results indicated that yttria doped in the ceria system,forming a good solid solution,readily induced more defects and oxygen vacancies that favored the improvement of catalytic activity and coking resistance.In the temperature range of 600-850℃,Ni/Ce0.90Y0.10O1.950 catalyst exhibited the best catalytic activity among the four tested catalysts,with the CH4 conversion,CO selectivity and H2 selectivity of 78.8%,90.6%and 89.8%,respectively,at 850℃.And the H2/CO molar ratio in products of Ni/Ce0.90Y0.10O1.950 catalyst was closer to the theoretical value of 2.0.The excellent coking resistant behaviors for all catalysts were clearly manifested by thermal analysis.
The catalytic properties of electrode materials Ni / Ce1-x YxO2-δ (x = 0.05,0.10,0.15 and 0.20) were investigated for partial oxidation of methane (POM). The CeO2-Y2O3 solid solutions were prepared by co-precipitaion method. The Nibased catalysts supported on the solid solutions were obtained using the impregnation method. Structural, surface and redox characteristics of the prepared catalysts were system-atically examined by means of X-ray diffraction (XRD), N2 adsorption-desorption (Brunauer-Emmet Teller BET method), H2 temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS) methods.The results indicated that yttria doped in the ceria system, forming a good solid solution, readily induced more defects and oxygen vacancies that favored the improvement of catalytic activity and coking resistance.In the temperature range of 600-850 ° C, Ni / Ce0.90Y0.10O1.950 catalyst exhibits the best catalytic activity among the four tested catalysts, with the CH4 conversion, CO selectivity and H2 The the H2 / CO molar ratio in products of Ni / Ce0.90Y0.10O1.950 catalyst was closer to the theoretical value of 2.0. The excellent coking resistant behaviors for all proves all apparently manifested by thermal analysis.