Ceo₂ Based Catalysts for the Treatment of Propylene in Motorcycle's Exhaust Gases.

In this work, the catalytic activities of several single metallic oxides were studied for the treatment of propylene, a component in motorcycles' exhaust gases, under oxygen deficient conditions. Amongst them, CeO₂ is one of the materials that exhibit the highest activity for the oxidation of C₃H₆. Therefore, several mixtures of CeO₂ with other oxides (SnO₂, ZrO₂, Co₃O₄) were tested to investigate the changes in catalytic activity (both propylene conversion and CO₂ selectivity). CeZrO₂, CeZrO₂ solid solutions and the mixtures of CeO₂ and Co₃O₄ was shown to exhibit the highest propylene conversion and CO₂ selectivity. They also exhibited good activities when tested under oxygen sufficient and excess conditions and with the presence of co-existing gases (CO, H₂O).