US3808323A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Purification of waste gases containing oxides of nitrogen and oxygen
Assignee: Engelhard Minerals and Chemicals Corp
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Filing: 1971-11-16
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Granted: 1974-04-30
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Expires: 1991-11-16
Abstract
Abstract WASTE GASES CONTAINING NITROGEN OXIDES AND OXYGEN ARE PURIFIED IN A CATALYTIC PROCESS IN WHICH A PORTION OF THE EFFLUENT FROM THE CATALYTIC REACTOR IS RECYCLED BACK TO THE INLET BY MEANS OF AN EJECTOR TO EFFECT CONTROLLED COMBUSTION IN THE REACTOR.
Inventors
- 👤 M Collins
- 👤 R Michalek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:24
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; Y; Y02; Y02C; Y02C20/00; Y02C20/20
Claims Analysis
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References Cited (Backward Citations)
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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) | 1977-04-29 | 1977-10-29 | 1978-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-29 | 1981-10-29 | 1982-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-29 | 1985-10-29 | 1986-04-30 | $7700.00 | Window Closed / Lapsed |