Patent US4338531A successfully refreshed from Google Patents.
Patent US3606986A successfully refreshed from Google Patents.
US3606986A
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US
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Copper-refining apparatus and the like
Assignee: WILLIAM B GREENBERG
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Filing: 1970-08-07
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Granted: 1971-09-21
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Expires: 1990-08-07
Abstract
Abstract THIS INVENTION IS ESPECIALLY CONCERNED WITH APPARATUS FOR THE PRODUCTION OF REFINED COPPER FROM SCRAP AND/OR OTHER IMPURE COPPER HAVING HIGH LEAD AND/OR TIN CONTENT WHEREIN SLAG FORMERS MAY BE SELECTED FROM COMPOUNDS OF BORATES, SILICATES, PHOSPHATES AND ALKALI OXIDES.
Inventors
- 👤 William B Greenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:22
CPC Classifications
C; C22; C22B; C22B15/00; C22B15/0026; C22B15/006; Y; Y10; Y10S; Y10S266/00; Y10S266/901
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) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |