The transition from Euro2 to Euro3 emission standards for passenger diesel vehicles requires very good hydrocarbon control coupled with moderate, passive NOx reduction. In some cases, CO and PM conversion is also required. Passive NOx reduction, that is, selective catalytic reduction of NOx by hydrocarbons without delivery of hydrocarbon specifically for this purpose, requires good management of a scarce hydrocarbon resource. At the same time, increased requirements for HC control demand that unconverted HC be further minimized. Appropriately designed lean NOx catalysts with hydrocarbon adsorber capabilities offer very good HC control with moderate NOx reduction performance when fresh. However, certain zeolite structures appear quite unstable under high temperature aging, yielding significant declines in aged NOx performance. Instabilities can be avoided through proper choice of molecular sieve structure and composition, together with suitable washcoat structure. Durable catalyst performance, exceeding Euro3 standards, will be shown, using a leased Euro:! vehicle.
Improvements in Intimately Coupled Diesel Hydrocarbon Adsorber/Lean NOx Catalysis Leading to Durable Euro 3 Performance
Sae Technical Papers
International Fall Fuels and Lubricants Meeting and Exposition ; 1998
1998-10-19
Conference paper
English
Automotive engineering | 1998
|Hydrocarbon adsorber technology
Automotive engineering | 2007
|Hydrocarbon Adsorber Technology
British Library Conference Proceedings | 2007
|Hydrocarbon Adsorber Technology
SAE Technical Papers | 2007
|A Durable In-Line Hydrocarbon Adsorber for Reduced Cold Start Exhaust Emissions
SAE Technical Papers | 1997
|