Patent US4061597A successfully refreshed from Google Patents.
US4061597A
Expired / Lapsed
US
⏱️ 0.0 years remaining
NOx control in catalyst manufacture
Assignee: Wyeth Holdings LLC
•
Filing: 1975-12-04
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Granted: 1977-12-06
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Expires: 1995-12-04
Abstract
Abstract An improved process for suppression of oxides of nitrogen arising from heat treatment of catalyst materials containing a source of such oxides is provided which comprises separately introducing the catalyst material and urea into the heating zone and then effecting heat treatment.
Inventors
- 👤 Marvin Sherwood Goldstein
- 👤 John Francis Lindsley
- 👤 William Woodrow Allison
- 👤 Charles Dan Price
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 01:21
CPC Classifications
B; B01; B01J; B01J37/00; B01J37/08; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01D53/9418; B01J37/0009; B01J37/0018; B01D2251/00; B01D2251/20; B01D2251/206; B01D2251/2067; B01D2255/00; B01D2255/20; B01D2255/207; B01D2255/20753; B01D2255/20769
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
93 words
A process for abating oxides of nitrogen which arise during heat treatment in the manufacture of catalysts containing a source of said oxides which process comprises introducing the catalyst material requiring heat treatment at a temperature of 300° C. and higher in said manufacture into a suitable heat treatment zone, separately introducing an effective amount of urea into said heat treatment zone, and thereafter effecting heat treatment at a temperature of 300° C. and higher whereby oxides of nitrogen arising from said catalyst material are abated by reaction with the separately introduced urea.
Claim 2
Dependent Claim
93 words
A process for abating oxides of nitrogen which arise during heat treatment in the manufacture of catalysts containing a source of said oxides which process comprises introducing the catalyst material requiring heat treatment at a temperature of 300° C. and higher in said manufacture into a suitable heat treatment zone, separately introducing an effective amount of urea into said heat treatment zone, and thereafter effecting heat treatment at a temperature of 300° C. and higher whereby oxides of nitrogen arising from said catalyst material are abated by reaction with the separately introduced urea.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein said urea is introduced in the form of a mist.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein said urea is introduced in solid form.
Claim 5
Dependent Claim
12 words
The process of claim 2 wherein said mist is an aqueous solution.
Claim 6
Dependent Claim
12 words
The process of claim 2 wherein said mist is pulverized solid urea.
Claim 7
Dependent Claim
12 words
The process of claim 3 wherein said urea is in prill form.
Claim 8
Dependent Claim
13 words
The process of claim 3 wherein said urea is carried on catalyst fines.
Claim 9
Dependent Claim
11 words
The process of claim 1 wherein said heat treatment is calcination.
Claim 10
Dependent Claim
16 words
The process of claim 1 wherein said catalyst material is one based on an alumina support.
Claim 11
Dependent Claim
22 words
The process of claim 1 wherein said catalyst material is one based on an alumina support and contains molybdenum and nickel activators.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-12-05 | 1981-06-06 | 1981-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-12-05 | 1985-06-06 | 1985-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-12-05 | 1989-06-06 | 1989-12-06 | $7700.00 | Window Closed / Lapsed |