US2039256A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of treating refinery sludges or slimes containing selenium and tellurium
Assignee: Individual
•
Filing: 1934-02-17
•
Granted: 1936-04-28
•
Expires: 1954-02-17
Abstract
No abstract record available.
Inventors
- 👤 Oliver C Martin
- 👤 Charles W Clark
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:43
CPC Classifications
C; C01; C01B; C01B19/00; C22; C22B; C22B15/00; C22B15/0002; C22B15/001; C22B15/0013; C22B15/0017
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) | 1939-04-28 | 1939-10-28 | 1940-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1943-04-28 | 1943-10-28 | 1944-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1947-04-28 | 1947-10-28 | 1948-04-28 | $7700.00 | Window Closed / Lapsed |