Schoenhaber, J., Richter, J., Despres, J., Schmidt, M. et al., "Advanced TWC Technology to Cover Future Emission Legislations," SAE Technical Paper 2015-01-0999, 2015, doi:10.4271/2015-01-0999.
The new emission regulations in Europe, EU 6 will promulgate more realistic driving conditions with more stringent HC, CO, NOx and particulate emissions. This legislation will also include the WLTP (Worldwide harmonized Light vehicles Test Procedure) cycle for CO2 measurements and a new requirement called “Real-Driving-Emissions” (RDE) as well. The RDE requirement is to ensure modern vehicles comply with the legislation under all conditions of normal driving. More robust aftertreatment solutions are needed to meet these new requirements. This work introduces an improved three-way catalyst (TWC) for gasoline engines for these new regulations. It is tested under static and dynamic conditions and on several engines and vehicles with various drive cycles. It offers better thermal stability combined with lower backpressure than former TWC generations. The new TWC has the potential to reduce NOx emission by 30% and most importantly the new TWC technology has improved CO/NOx conversion efficiency under high dynamic driving conditions. Finally, this work will show that the oxygen storage capacity (OSC) of the new TWC technology is optimized for diagnostics.