US4282115A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalyst for selectively reducing nitrogen oxides from oxygen-containing exhaust gases
Assignee: Mitsubishi Heavy Industries Ltd
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Filing: 1980-02-01
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Granted: 1981-08-04
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Expires: 2000-02-01
Abstract
Abstract A catalyst for the selective catalytic reduction of nitrogen oxides by the use of ammonia as a reducing agent composed of a catalytically active constituent on a carrier having a honeycomb or parallel plate structure, the carrier being prepared from a slurry of crystallized calcium silicate prepared by mixing silicic acid and lime and heating the mixture under pressure, the calcium silicate having the structure of xonotrite and the formula 6 CaO.6 SiO 2 . H 2 O.
Inventors
- 👤 Masumi Atsukawa
- 👤 Yoshihiko Nishimoto
- 👤 Naruo Yokoyama
- 👤 Toshikuni Sera
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:40
CPC Classifications
B; B01; B01J; B01J37/00; B01J37/04; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01D53/9418; B01J23/00; B01J23/16; B01J23/20; B01J23/22; B01J23/70; B01J27/00; B01J27/02; B01J27/053; B01D2251/00; B01D2251/20; B01D2251/206; B01D2251/2062; B01D2255/00; B01D2255/20; B01D2255/207; B01D2255/20723; B01D2255/20738; B01D2255/20761; B01D2258/00; B01D2258/01; B01D2258/012; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149; Y10T428/24165
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
68 words
A catalyst for the treatment of exhaust gases containing soot and dust comprising a catalytically active constituent on a carrier in having a honeycomb or parallel plate structure, said carrier being prepared from a slurry of crystallized calcium silicate prepared by mixing silicic acid and lime and treating the mixture under pressure, said calcium silicate having the structure of xonotrite and the formula: 6CaO.6SiO 2 .H 2 O.
Claim 2
Dependent Claim
68 words
A catalyst for the treatment of exhaust gases containing soot and dust comprising a catalytically active constituent on a carrier in having a honeycomb or parallel plate structure, said carrier being prepared from a slurry of crystallized calcium silicate prepared by mixing silicic acid and lime and treating the mixture under pressure, said calcium silicate having the structure of xonotrite and the formula: 6CaO.6SiO 2 .H 2 O.
Claim 3
Dependent Claim
27 words
The catalyst of claim 1, wherein the catalytically active constituent is selected from the group consisting of oxides and sulfates of iron, copper, vanadium and combinations thereof.
Claim 4
Dependent Claim
35 words
The catalyst of claim 1, wherein the carrier carries V 2 O 5 together with an additional constituent selected from the group consisting of MoO 3 , Co 2 O 3 and WO 3 .
Claim 5
Dependent Claim
30 words
The catalyst of claim 3, wherein the carrier's prepared by adding ZrO 2 in amounts such that the carrier contains from 5 to 50 wt % of ZrO 2 .
Claim 6
Dependent Claim
21 words
The catalyst of claim 1, wherein the carrier carries TiO 2 of the anatase type and V 2 O 5 .
Claim 7
Dependent Claim
48 words
The catalyst of claim 1, wherein the carrier carries a composition of 2 to 5 wt % V 2 O 5 , 1 to 10 wt % of MoO 3 , Co 2 O 3 or WO 3 with the balance being TiO 2 or ZrO 2 .
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) | 1984-08-03 | 1985-02-02 | 1985-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-03 | 1989-02-02 | 1989-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-03 | 1993-02-02 | 1993-08-04 | $7700.00 | Window Closed / Lapsed |