Patent US3864450A successfully refreshed from Google Patents.
US3864450A
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US
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Process for removing nitrogen oxides from gaseous mixtures
Assignee: Toray Industries Inc
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Filing: 1972-06-23
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Granted: 1975-02-04
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Expires: 1992-06-23
Abstract
Abstract Removal of nitrogen oxides from waste gases by contacting the waste gases with hot carbon which contains sodium hydroxide and/or potassium hydroxide.
Inventors
- 👤 Tetsu Takeyama
- 👤 Ryoh Endoh
- 👤 Keizo Masuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:50
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/02; B01J23/04; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9413; B01D53/9418; B01D2255/00; B01D2255/20; B01D2255/202; B01D2255/2022; B01D2255/2027; B01D2255/70; B01D2255/702
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
67 words
IN A PROCESS FOR THE REMOVAL OF A NITROGEN OXIDE IMPURITY FROM A GASEOUS MIXTURE, WHEREIN THE GASEOUS MIXTURE SUBJECTED TO THE TREATMENT CONTAINS BOTH A NITROGEN OXIDE IMPURITY AND OXYGEN, THE STEPS COMPRISING CONTACTING THE GASEOUS MIXTURE WITH A CATALYST CONSISTING ESSENTIALLY OF CARBON IMPREGNATED WITH SODIUM HYDROXIDE OR POTASSIUM HYDROXIDE, WHILE MAINTAINING SAID CATALYST AT A TEMPERATURE IN THE RANGE FROM ABOUT 250*C. TO 480*C.
Claim 2
Dependent Claim
67 words
IN A PROCESS FOR THE REMOVAL OF A NITROGEN OXIDE IMPURITY FROM A GASEOUS MIXTURE, WHEREIN THE GASEOUS MIXTURE SUBJECTED TO THE TREATMENT CONTAINS BOTH A NITROGEN OXIDE IMPURITY AND OXYGEN, THE STEPS COMPRISING CONTACTING THE GASEOUS MIXTURE WITH A CATALYST CONSISTING ESSENTIALLY OF CARBON IMPREGNATED WITH SODIUM HYDROXIDE OR POTASSIUM HYDROXIDE, WHILE MAINTAINING SAID CATALYST AT A TEMPERATURE IN THE RANGE FROM ABOUT 250*C. TO 480*C.
Claim 3
Dependent Claim
18 words
The process according to claim 1 wherein the reaction temperature is between about 350* C and 450* C.
Claim 4
Dependent Claim
38 words
The process according to claim 1 wherein the concentration of said alkali metal hydroxide contained in the carbon catalyst is from about 2.0 to 20.0 percent by weight of metal based upon the weight of the original carbon.
Claim 5
Dependent Claim
21 words
The process according to claim 1 wherein the carbon is selected from the group consisting of coke, semi-coke, and petroleum coke.
Claim 6
Dependent Claim
34 words
The process according to claim 1 wherein the gaseous mixture is passed through the catalyst bed at a space velocity from about 6,000 to 80,000 volumes of gas per volume of catalyst per hour.
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) | 1978-02-03 | 1978-08-05 | 1979-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-03 | 1982-08-05 | 1983-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-03 | 1986-08-05 | 1987-02-04 | $7700.00 | Window Closed / Lapsed |