Search Results

The second stage of the PROCONVE emission legislation, which is effective since model year 1992, was met by various of the Brazilian carmakers through the application of open loop three-way catalysts. As a result of intensive test and development programs, different open loop three-way catalyst designs were selected for ethanol and gasohol fueled vehicles, so as to reach the required emission reduction performance at optimized costs. For the ethanol fueled vehicles, the new washcoats developed allowed precious metal formulations without rhodium. The durability of these systems is supported by the properties of the fuel, since ethanol is basically free of sulphur and lead. For the gasohol fueled vehicles, a Pd/Rh formulation is applied, along with washcoats which guarantee an emission reduction performance in a broad range of A/F engine operation conditions.