Exhaust gas purifying catalyst and exhaust gas purifying process
US5154902A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 3, 1991 |
| Grant date | Oct 13, 1992 |
| Priority date | — |
| Expiry date | Apr 3, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2255/30
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust gas purifying catalyst of this invention is a catalyst for mainly removing nitrogen oxides contained in exhaust gases, comprising: crystalline copper silicate expressed by the following composition formula; M.sub.n+m (Cu.sub.n Al.sub.m Si.sub.96-n-m O.sub.192).16H.sub.2 O, where M denotes one of sodium (Na) and potassium (K), and n+m<27. An exhaust gas purifying process of this invention employs the above-mentioned crystalline copper silicate catalyst. The exhaust gas purifying catalyst and the exhaust gas purifying process employing the same purify the nitrogen oxides (NOx) by facilitating the reaction between hydrocarbons (HC) and nitrogen oxides (NOx) contained in the exhaust gases more preferentially than the reaction between hydrocarbons (HC) and oxygen (O.sub.2) contained therein, thereby purifying the nitrogen oxides (NOx) and hydrocarbons (HC) at high efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.