US2645664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of selenium
Assignee: Distillers Co Yeast Ltd
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Filing: 1949-07-11
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Granted: 1953-07-14
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Expires: 1969-07-11
Abstract
No abstract record available.
Inventors
- 👤 Hadley David James
- 👤 Heap Robert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:02
CPC Classifications
C; C07; C07C; C07C45/00; C07C45/27; C07C45/32; C07C45/33; C07C45/34; C01; C01B; C01B19/00; C01B19/02; C07C45/35
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
91 words
IN THE PROCESS OF OXIDISING OLEFINES WITH FREE OXYGEN-CONTAINING GASES BY PASSING THE MIXTURE IN THE PRESENCE IN THE REACTION ZONE OF ELEMENTARY SELENIUM OVER A COPPER CONTAINING CONTACT MATERIAL TO PRODUCE THEREBY UNSATURATED ALDEHYDES AND COOLING THE GASEOUS MIXTURE ISSUING FROM SAID REACTION ZONE, WHEREBY A DEPOSIT CONSISTING ESSENTIALY OF SELENIUM AND SELENIUM OXIDE IS FORMED, THE STEP OF RECOVERING ELEMENTARY SELENIUM FROM THE SAID DEPOSIT CONTAINING SELENIUM AN DSELEIUM OXIDE WHICH CONSISTS OF SUBJECTING SAID DEPOSIT TO A HEAT TREATMENT AT TEMPERATURES EXCEEDING 240* C. IN AN INERT ATMOSPHERE.
Claim 2
Dependent Claim
91 words
IN THE PROCESS OF OXIDISING OLEFINES WITH FREE OXYGEN-CONTAINING GASES BY PASSING THE MIXTURE IN THE PRESENCE IN THE REACTION ZONE OF ELEMENTARY SELENIUM OVER A COPPER CONTAINING CONTACT MATERIAL TO PRODUCE THEREBY UNSATURATED ALDEHYDES AND COOLING THE GASEOUS MIXTURE ISSUING FROM SAID REACTION ZONE, WHEREBY A DEPOSIT CONSISTING ESSENTIALY OF SELENIUM AND SELENIUM OXIDE IS FORMED, THE STEP OF RECOVERING ELEMENTARY SELENIUM FROM THE SAID DEPOSIT CONTAINING SELENIUM AN DSELEIUM OXIDE WHICH CONSISTS OF SUBJECTING SAID DEPOSIT TO A HEAT TREATMENT AT TEMPERATURES EXCEEDING 240* C. IN AN INERT ATMOSPHERE.
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) | 1956-07-13 | 1957-01-12 | 1957-07-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-07-13 | 1961-01-12 | 1961-07-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-07-13 | 1965-01-12 | 1965-07-14 | $7700.00 | Window Closed / Lapsed |