US4052337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalyst for reduction of nitrogen oxides and process for preparing same
Assignee: Tonen General Sekiyu KK
•
Filing: 1976-03-19
•
Granted: 1977-10-04
•
Expires: 1996-03-19
Abstract
Abstract Nitrogen oxides are removed from gaseous mixtures comprising the same by contacting with a catalyst comprising a base metal component carried on a natural or synthetic zeolite in the presence of ammonia. The alkali metal content of the zeolite is carefully controlled through ion exchange with an alkaline earth metal compound.
Inventors
- 👤 Eiichiroh Nishikawa
- 👤 Takuji Itoh
- 👤 Tsugio Maeshima
- 👤 Setsuo Kamiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:56
CPC Classifications
B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/061; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; B01D53/8628
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
117 words
A process for preparing a catalyst for reduction of nitrogen oxides, characterized in that: a. a synthetic crystalline aluminosilicate is contacted with a solution containing one or more alkaline earth metal ions to ion-exchange the alkali metals in the synthetic crystalline aluminosilicate with the alkaline earth metal(s) so that the alkali metal content remaining will be within the range from 0.2 to 0.6 equivalents per gram atom of alumina; (b) the ion-exchanged synthetic crystalline aluminosilicate is calcined, if necessary; and (c) the synthetic crystalline aluminosilicate is contacted with a solution containing one or more active metal ions having an effect of reducing nitrogen oxides, whereby the active metal component(s) is (are) carried on the aluminosilicate by impregnation.
Claim 2
Dependent Claim
117 words
A process for preparing a catalyst for reduction of nitrogen oxides, characterized in that: a. a synthetic crystalline aluminosilicate is contacted with a solution containing one or more alkaline earth metal ions to ion-exchange the alkali metals in the synthetic crystalline aluminosilicate with the alkaline earth metal(s) so that the alkali metal content remaining will be within the range from 0.2 to 0.6 equivalents per gram atom of alumina; (b) the ion-exchanged synthetic crystalline aluminosilicate is calcined, if necessary; and (c) the synthetic crystalline aluminosilicate is contacted with a solution containing one or more active metal ions having an effect of reducing nitrogen oxides, whereby the active metal component(s) is (are) carried on the aluminosilicate by impregnation.
Claim 3
Dependent Claim
14 words
The process of claim 1 wherein the alkaline earth metal ion is calcium ion.
References Cited (Backward Citations)
US3436356A
Cited
US3476508A
Cited
US3498928A
Cited
US3346328A
Cited
US3689212A
Cited
US3895094A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-03 | 1981-04-04 | 1981-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-03 | 1985-04-04 | 1985-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-03 | 1989-04-04 | 1989-10-04 | $7700.00 | Window Closed / Lapsed |