Development of Advanced Platinum-Rhodium Catalyst for Future Emissions Requirements

In order to meet future emission standards for gasoline vehicles, catalyst designers have developed thermally durable three-way catalysts with enhanced activity. The most effective catalysts for achieving the required hydrocarbon conversion were those containing high levels of palladium. This has led to increased levels of palladium being used. Recent palladium price fluctuations have created interest in the possibility of using advanced platinum-based technologies. The performance of a new platinum-rhodium three-way catalyst (TWC) was compared with an advanced palladium-rhodium catalyst on an engine test-bed. The results showed the new platinum-rhodium catalyst gave equivalent, or better, performance at similar total precious metal cost. The performance on selected vehicles confirmed future emissions standards can be achieved with platinum-based catalysts.