Methane combustion over Co3O4/YSZ-γ-Al2O3+CYZ monolithic catalysts

A series of cobalt-based monolithic catalysts supported on mixture of YSZ-gamma-Al2O3 and CeO2-Y2O3-ZrO2 were prepared by impregnation method, and characterized by XRD, XPS, BET and H-2-TPR. Contrasting with the 8 wt% Co3O4-based monolithic catalyst supported on YSZ-gamma-Al2O3 or CeO2-Y2O3-ZrO2, the catalytic activities for methane combustion were assessed in a micro-reactor. All the mixture supported monolithic catalysts had higher activity for methane combustion than the contrast catalysts. After calcination at 1000 degrees C for 5 h, the monolithic catalysts remained highly active and very stable, especially the catalyst containing 8 wt% Of Co3O4 had the highest activity and methane was completely converted to CO2 at ca. 514 degrees C. The results showed that the mixture had the advantage of CeO2-Y2O3-ZrO2 and YSZ-gamma-Al2O3 (gamma-Al2O3 modified by Y2O3 and ZrO2) and can resist forming the crystal of CoAl2O4 effectively.