Correlation between catalytic selectivity and oxygen storage capacity in autothermal reforming of methane over Rh/Ce0.45Zr0.45RE0.1 catalysts (RE = La, Pr, Nd, Sm, Eu, Gd, Tb)

Trivalent rare-earth (RE = La, Pr, Nd, Sm, Eu, Gd, Tb)-doped Ce0.45Zr0.45RE0.1 solid solutions were synthesized via reverse micro-emulsion method and the catalytic performance of the Rh-supported catalysts was investigated in autothermal reforming of methane (ATR). It was found that CH4 conversion went through a maximum as a function of oxygen storage capacity (OSC) value of the support. Higher OSC will help to enhance the reactivity toward water-gas-shift (WGS) reaction, resulting higher H-2/CO ratio. A striking correlation between OSC and H-2/CO ratio was observed, which presented a maximum for the Rh/CZLa (3.4) and a minimum for the Rh/CZTb (2.6) catalysts. (C) 2009 Elsevier B. V. All rights reserved.