EFFECTS OF RARE EARTH OXIDES ON PERFORMANCES OF Ni/AlO CATALYSTS FOR METHANE STEAM REFORMING REACTION

<正>The Catalytic performances for methane steam reforming reaction ofNi/Al2O3（commercial）, Ni/Al2O3 （developed surface ）and Ni/Al2O3-RxOy （R israre earth oxide） Catalysts were investigated by means of X-ray diffraction,TG, SEM/ X-ray analysis, pulse gas chromatography,BET and Mercuryporsiniter techniques. The distribution of rear earth oxides on the supports,themetal-support （additives） interaction and the influence of rare earth oxideadditives on the dispersion of active components,catulytic activities,variationof nickel crystallites size,CO chemisorption,formation of NiAl2O4 as well asthe reducibility of the catalysts were examined.The presence of rare earthoxides in the Ni/Al2O3 （developed surface） results in great improvement ofstubility through suppressing the growth of Ni crystallites,the oxidation of themetallic Ni and the formation of NiAl2O4. The effect of heavy rare earth oxidesis more distinct than that of the light ones.Strong metal support interaction（SMSI） exists in Ni/Al2O3- R