(227e) Advanced Emission Control Strategies for Gasoline Engines with Special Emphasis on the Development of Pd-Based Technologies

Nunan, J., Umicore Autocat USA Inc.

In the current paper we will review the most important developments in gasoline emission control.  This includes the introduction of advanced support materials and promoters for improved performance, greater durability and ultimately the use of lower Precious Group Metal (PGM) loadings while still meeting stringent emission standards.  The development of Pd-based technologies will be discussed in detail and the effective incorporation of Pd into multi-catalyst/converter concepts.  The implementation of Pd in Three-Way-Conversion (TWC) catalysts reflects one of the most important developments pioneered by Dr Gandhi and his colleagues at the Ford R&D laboratories.  This required a detailed understanding of the detrimental effects of S and Pb on the performance of Pd.  The development of specialized support materials that enhance & modify the performance of Pd allowing it to perform the catalytic functions specific to the more expensive PGM - Rh for NOx control will be reviewed. The latest approaches in achieving the more stringent ULEV, SULEV and LEV-III emission standards will be discussed.