Exhaust gas purification apparatus of internal combustion engine and catalyst for purifying exhaust gas of internal combustion engine
US6397582B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 2000 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Jul 20, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust gas purification apparatus for use in an internal combustion engine comprises an exhaust gas duct connected to the engine through which the exhaust gas containing NOx gas passes and a catalyst so disposed in the exhaust gas duct that it contacts with the exhaust gas. The catalyst chemically adsorbs NOx under the condition that a stoichiometric amount of a gaseous oxidizing agent present in the exhaust gas is larger than that of a gaseous reducing agent present in the exhaust gas for reducing NOx, while NOx being adsorbed is catalytically reduced in the presence of the reducing agent under the condition that the stoichiometric amount of the oxidizing agent is not larger that of the reducing agent. Thereby, NOx the lean burn exhaust gas in the engine can be effectively made harmlessly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.