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US4564604A
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Catalyst for treating waste gases
Assignee: Mitsubishi Heavy Industries Ltd
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Filing: 1984-11-15
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Granted: 1986-01-14
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Expires: 2004-11-15
Abstract
Abstract A catalyst for treating waste gases comprising nitrogen oxides, which catalyst comprises a protonized zeolite coating formed on the surface of a catalytic ingredient. This type of catalyst has a prolonged life and is very useful in treating waste gases comprising nitrogen oxides by adding ammonia to the waste gas and reducing the nitrogen oxides in the waste gas with the catalyst to render the nitrogen oxides non-noxious.
Inventors
- 👤 Kozo Iida
- 👤 Yoshiaki Obayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:33
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; B01D53/8628; B01J; B01J37/00; B01J37/02; B01J37/024; B01J37/0246; B01J21/00; B01J21/06; B01J21/063; B01J23/00; B01J23/16; B01J23/20; B01J23/22; B01J23/24
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
62 words
A catalyst for treating waste gases comprising nitrogen oxides by a process which comprises adding ammonia to the waste gas and reducing the nitrogen oxides with catalytic ingredients of the catalyst to render the nitrogen oxides into non-noxious compounds, the catalyst comprising a catalytic ingredient for nitrogen oxides and a coating formed on the catalytic ingredient and consisting of a protonized zeolite.
Claim 2
Dependent Claim
62 words
A catalyst for treating waste gases comprising nitrogen oxides by a process which comprises adding ammonia to the waste gas and reducing the nitrogen oxides with catalytic ingredients of the catalyst to render the nitrogen oxides into non-noxious compounds, the catalyst comprising a catalytic ingredient for nitrogen oxides and a coating formed on the catalytic ingredient and consisting of a protonized zeolite.
Claim 3
Dependent Claim
19 words
The catalyst according to claim 1, wherein said coating is in a thickness of from 10 to 50 μm.
Claim 4
Dependent Claim
18 words
The catalyst according to claim 1, wherein said zeolite is zeolite X, zeolite Y, zeolite ZSM-5 or mordenite.
Claim 5
Dependent Claim
15 words
The catalyst according to claim 1, wherein said catalytic ingredient is supported on a carrier.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-13 | 1989-07-15 | 1990-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-13 | 1993-07-15 | 1994-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-13 | 1997-07-15 | 1998-01-14 | $7700.00 | Window Closed / Lapsed |