Zirconia supported Ru-Co bimetallic catalysts for diesel soot oxidation

Various amounts of ruthenia-cobaltate bimetallic catalyst supported on zirconia have been prepared by co-impregnation method and their catalytic activity towards soot/carbon oxidation has been evaluated using TG technique under the loose contact condition. These catalysts show good activity for carbon/soot oxidation, which is observed to be a factor of ruthenia content. The thermal stability experiments confirmed the stability of catalytic materials in air at least up to 900 degrees C. In this way, ruthenia can be easily dispersed on zirconia possibly through the solid solution formation, while its thermal stability can be significantly improved by introducing a transition metal namely cobalt. Formation of Ru-Co bimetallic clusters over zirconia is probably responsible for its thermal stability, while dissociative adsorption of oxygen on catalyst surface appears to be responsible for their catalytic activity.