Method of treating diesel exhaust gases
US6813884B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2002 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | Jan 29, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N2610/08
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A diesel exhaust treatment system and method of oxidizing NO to NO2 at low temperatures are provided. The system utilizes a platinum catalyst on a zirconia-stabilized silica support which oxidizes NO in the exhaust gas to NO2 and uses the NO2 in an amount sufficient to oxidize particulate trapped on a particulate filter. The catalyst is preferably pre-treated at a temperature of between about 500 to 650° C. in a NO-oxygen-nitrogen mixture to increase conversion at low temperatures. The catalyst preferably includes an additional oxide component selected from the group consisting of TiO2, P2O5, WO3, B2O3, and Al2O3. or a heteropolyacid component to further increase activity at low temperatures or to decrease platinum loading at the same level of performance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.