Etude par spectrometrie d'absorption X d'un catalyseur de depollution automobile sous melange gazeux simulant un gaz d'echappement

摘要

The operation of an alumina supported Pt-Rh three-way catalyst has been studied under oscillating gas mixtures. An in situ EXAFS study of the catalyst has shown that there is a transient deactivation during the oxidising excursion associated with the rhodium component which becomes partially oxidised to its inactive form RJ12O3. The platinum, on the other hand, remains reduced during the course of the reaction and is able to maintain the activity in an oxidising environment.