An overview of kinetic and spectroscopic investigations on three-way catalysts: mechanistic aspects of the CO + NO and CO + N2O reactions

✍ Scribed by P. Granger; C. Dujardin; J.-F. Paul; G. Leclercq

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 668 KB
• Volume: 228
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/j.molcata.2004.09.081

✦ Synopsis

This paper deals with the kinetics of the reduction of nitric oxides by CO, which is a major reaction involved in automotive exhaust three-way catalysts. Spectroscopic and steady state kinetic measurements have been compared in order to explain the different selectivity behavior of Pt-and Rh-based catalysts, particularly during the cold start. It was found that in situ spectroscopy can be a useful tool either for stating on the nature of intermediates or checking the validity of a rate equation. Regarding the kinetics, subsequent calculations and comparisons of thermodynamic and kinetic parameters provide relevant information for modeling purposes. Also, it was found that our kinetic results can be correlated to surface modifications in the particular case of supported bimetallic Pt-Rh catalysts.