Steam reforming of ethanol over Co3O4/CeO2 catalysts prepared by different methods

In this paper, Co3O4/CeO2 catalysts for steam reforming of ethanol (SRE) were prepared by co-precipitation and impregnation methods. The catalysts prepared by co-precipitation were very active and selective for SRE. Over 10%Co3O4/CeO2 catalyst, ethanol conversion was close to 100% and hydrogen selectivity was about 70% at 450 °C. The catalysts were characterized by X-ray diffraction, temperature-programmed reduction (TPR) and BET surface area measurements. The preparation method influenced the interaction between cobalt and CeO2 evidently. The incorporation of Co ions into CeO2 crystal lattice resulted in weaker interaction between cobalt and ceria on catalyst surface. In comparison with catalysts prepared by impregnation, more cobalt ions entered into CeO2 lattice, and resulted in weaker interaction between active phase and ceria on surface of Co3O4/CeO2 prepared by co-precipitation. Thus, cobalt oxides was easier to be reduced to metal cobalt which was the key active component for SRE. Meanwhile, the incorporation of Co ions into CeO2 crystal lattice was beneficial for resistance to carbon deposition.