Method and apparatus for desulfating a NO.sub.x trap
US5758493A · kind A · utility
102Cited by
19References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 13, 1996 |
| Grant date | Jun 2, 1998 |
| Priority date | — |
| Expiry date | Dec 13, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method and apparatus for desulfating a NO.sub.x trap is proposed wherein half of the engine cylinders are operated at a rich air/fuel ratio and half are operated at a lean A/F during the desulfation process. The two exhaust gas streams, the rich stream and the lean stream, are physically or chemically separated until they enter the NO.sub.x trap. A catalyzed exothermic chemical reaction is then generated in the trap. The resulting temperature increase is sufficient to remove SOX from the trap. During desulfation spark advance is adjusted to minimize event time imbalance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.