Browse Publications Technical Papers 2005-01-1087

NOx-Particulate Filter (NPF) vs. NOx Storage Catalyst (NSC): Evaluation of an After-Treatment Concept to Meet Future Diesel Emission Standards 2005-01-1087

Simultaneous particulate and NOx reduction represent the next step in the reduction of diesel emissions. One of the most promising concepts to achieve this target involves the combination of two technologies already in use in the after-treatment technology: Diesel Particulate Filter and NOx Storage Catalyst. One of the most controversial points is the possibility to integrate these two functions in the same component, the so called NOx Particulate Filter (NPF). The first purpose of this project was to compare NOx Storage Catalysts (NSC) and NPF in terms of overall efficiency, especially in terms of changes of the NOx absorption efficiency over the cross section of the catalyst. The results showed a better behavior of the NPF. Theories concerning the reasons are provided, even if further investigations to fully explain this phenomenon are still necessary. As a second step, the NOx emissions for the NPF were analyzed during a test cycle with simple NOx regeneration (DeNOx) and combined soot and NOx regenerations (DeSoot- DeNOx), showing an overall NOx reduction capability of around 50%. Finally, different strategies to reduce temperature peaks and NOx slip were implemented. The timing of the rich spikes during DeSoot operation was optimized in order to reduce the NOx release.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 16% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:

Impact of Aging and NOX/Soot Ratio on the Performance of a Catalyzed Particulate Filter for Heavy Duty Diesel Applications


View Details


The Application of a NOx Absorber Catalyst System on a Heavy-Duty Diesel Engine


View Details


The Second Generation of Catalyzed Diesel Particulate Filter Systems for Passenger Cars - Particulate Filters with Integrated Oxidation Catalyst Function-


View Details