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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.

With the growing awareness about the presence of fine/ultra fine particulates in the ambient air and their negative impact on climate and health, some regions of the world have started to look closer at the contribution of road traffic. Since Gasoline engines, in particular when injecting fuel directly into the combustion chamber, proved to emit relevant numbers of particulates, even hardly visible, the growing share of Gasoline DI engines and their small size of particulate emissions is a concern. To address the same, the EU has already set limits for the particulate number with EU6 from 2015 onwards. The US considers setting challenging limits by particulate mass. Since mass of ultra fine particulates is very low and difficult to measure, experts investigate if a measurement by number might better address the particular concern. The implementation of a coated Particulate Filter enables meeting not only basic demands during traditional emission test cycles.

With the introduction of limits for particle numbers besides particle mass emitted by light duty vehicles new pollution control devices like catalyzed gasoline particulate filters (GPF) might be required. GPFs need to address the challenge to provide sufficient particle number reduction at acceptable pressure drop in addition while having high conversion efficiencies for regulated pollutants. The emission performance of gasoline particulate filters coated with a three-way functional washcoat was examined. The impact of the washcoat on particle filtration efficiency was investigated, as well as its impact on the conversion efficiencies for hydrocarbons, carbon monoxide and nitrous oxides. Moreover, it was found that the precious metal containing washcoat accelerates the regeneration of a filter when loaded with artificial soot.