Temperature-Programmed Reduction Studies of Al2 O3-Supported Pt/Rh Catalysts

This paper presents temperature programmed reduction (TPR) results or Al₂O₃-supported Pt/Rh bimetallic catalysts. Our results indicate that Rh undergoes harmful interactions with the Al₂O₃ support under high-temperature oxidizing conditions regardless of whether Pt was present in the catalyst. This Rh-Al₂O₃ interactions renders the Rh irreducible in 5% H₂ at temperatures below 600°C. These results suggest that the mechanism of oxidative deterioration of bimetallic Pt/Rh catalyst is substantially similar to the deterioration mechanism for monometallic Rh/Al₂O₃ catalysts.