On-board diagnostic method for NO2 formation in an oxidation catalyst
US9181843B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2012 |
| Grant date | Nov 10, 2015 |
| Priority date | — |
| Expiry date | Dec 29, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The capacity of a platinum-containing diesel oxidation catalyst (DOC) to simultaneously convert NO to NO2, CO to carbon dioxide, and remaining hydrocarbons to carbon dioxide and water in the exhaust system of a vehicle diesel engine may be evaluated and diagnosed using measured DOC exhaust inlet temperatures and outlet temperatures at a relatively high exhaust temperature and, soon thereafter, at a relatively low exhaust inlet temperature. Values of the platinum-containing DOC exotherms at the high and low DOC inlet temperatures are found to provide a basis for evaluation of both NO conversion and the HC and CO conversion capabilities of the DOC. The process may be repeated as the catalyzed DOC conversion efficiency changes with use. The practice may also be used to evaluate the performance of oxidation catalysts used in a like way in treating the exhaust from a lean-burn gasoline engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.