Process for reducing nitrogen oxides
US5543124A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1994 |
| Grant date | Aug 6, 1996 |
| Priority date | — |
| Expiry date | Oct 20, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N2610/04
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for efficiently reducing nitrogen oxides in exhaust gases including excess oxygen. The process includes intermittently introducing a reducing agent, such as hydrogen and carbon monoxide, for reducing nitrogen oxides to a reducing catalyst, such as platinum, disposed in an exhaust gas passage while maintaining an oxygen excess condition. The reducing agent is intermittently introduced in a manner to satisfy the following equation: [NO.sub.x ]<[H.sub.2 ]+[CO], wherein [H.sub.2 ], [CO] and [NO.sub.x ] are molar concentrations of hydrogen, carbon monoxide and nitrogen oxides, respectively. The reducing catalyst may include a transition metal, an alkaline metal and/or an alkaline earth metal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.