Technical Paper
High Temperature Durable Three-way Catalysts to Meet European Stage IV Emission Requirements
2002-03-04
2002-01-0351
By characterizing current three-way catalysts (TWCs) after thermal aging, it was possible to use the information obtained to develop a new generation of more thermally durable TWCs. To assess their performance, a dynamic dynamometer was used to age these new TWC formulations (Pt/Rh and Pd/Rh) at a series of different maximum catalyst operating temperature limits (960, 1010 and 1050°C) using a proprietary transient aging cycle. Each catalyst was evaluated periodically throughout the aging on a dynamic dynamometer to assess its emission performance and aging characteristics. After a representative aging time, both the Pt/Rh and the Pd/Rh formulations were capable of meeting European Stage IV emission standards on a production powertrain after prolonged 1050°C aging. The thermal resistance of the new Pt/Rh and Pd/Rh TWCs is significantly better than that of previous technologies.
