Patent US3705231A successfully refreshed from Google Patents.
US3705231A
Expired / Lapsed
US
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Selective removal of nitrogen dioxide from gases
Assignee: BASF SE
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Filing: 1970-07-21
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Granted: 1972-12-05
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Expires: 1990-07-21
Abstract
Abstract NITROGEN DIOXIDE IS SELECTIVELY REMOVED FROM GASES WHICH CONTAIN NOT ONLY NITROGEN DIOXIDE IN STRONGLY DILUTED FORM BUT ALSO OXYGEN BY REACTION WITH CARBON MONOXIDE AT ELEVATED TEMPERATURES IN THE PRESENCE OF SUPPORTED CATALYSTS OF PLATINUM AND/OR PALLADIUM. THE REACTION TAKES PLACE AT TEMPERATURES OF FROM 130* TO 425* C. AND THE CARRIER USED IS A-ALUMINUM OXIDE OR SILICON DIOXIDE. THE RATIO OF THESE OXIDES TO ONE ANOTHER IS CHOSEN IN ACCORDANCE WITH THE PREDETERMINED TEMPERATURE.
Inventors
- 👤 Gerhard Biberacher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:25
CPC Classifications
C; C01; C01B; C01B21/00; C01B21/20; C01B21/24; B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; B01D53/8628; Y; Y02; Y02A; Y02A50/00; Y02A50/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-12-05 | 1976-06-05 | 1976-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-05 | 1980-06-05 | 1980-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-05 | 1984-06-05 | 1984-12-05 | $7700.00 | Window Closed / Lapsed |