Study On Preparation And Performance Of Practical Co-Base Monolithic Catalyst For Methane Combustion

A series of cobalt-based catalysts had been prepared with supports γ-Al2O3, OSM(oxygen storage materials,CeO2-Y2O3- ZrO2), YSZ-Al2O3(γ- Al2O3 modified by Y2O3 and ZrO2) and mixed YSZ-Al2O3+OSM using impregnation method and were coated on the surface of cordierite. The catalytic activities and ageing resistant performance of above catalysts for methane combustion was evaluated in a continuous-flow micro-reactor. They were also characterized by XRD, XPS, BET and H2-TPR.The results showed that after aging at 1000℃, Co3O4/γ-Al2O3 almost lost its activity, but Co3O4/ YSZ-Al2O3, Co3O4/ YSZ-Al2O3+OSM could still remained its activities. The results of XRD, XPS showed that the reason of low activity of Co3O4/γ-Al2O3 to α-Al2O3 was the formation of crystal of CoAl2O4 and transformation of γ-Al2O3. While there were almost no CoAl2O4 formation and transformationα-Al2O3 in the catalysts of Co3O4/ YSZ-Al2O3, Co3O4/ YSZ-Al2O3+OSM. Both fresh and aged Co3O4/ YSZ-Al2O3 and Co3O4/ YSZ-Al2O3+OSM remain high specific surface area .While for Co3O4/ OSM specific surface area is only 8.5m2/g after aged 1000℃. Among Co3O4/ YSZ-Al2O3+OSM with different Co3O4 loading , 8 wt.% Co3O4/ YSZ-Al2O3+OSM is most active and stable. Both Co3O4+Fe2O3/YSZ-Al2O3+OSM and Co3O4+Fe2O3+MnO2/YSZ-Al2O3+OSM are active and stable. But Co3O4+Fe2O3+MnO2/YSZ-Al2O3+OSM exhibits the highest activity and stability. The combustion stove equipped with Co3O4+Fe2O3+ MnO2/YSZ- Al2O3+OSM catalyst had high thermal efficiency and low pollution emitting.