Patent US2579531A successfully refreshed from Google Patents.
US2579531A
Expired / Lapsed
US
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Process for extracting gold and silver
Assignee: Individual
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Filing: 1949-11-16
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Granted: 1951-12-25
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Expires: 1969-11-16
Abstract
No abstract record available.
Inventors
- 👤 Zadra John Benjamin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:48
CPC Classifications
C; C01; C01G; C01G7/00; C01G7/003; C01G5/00; C01G5/003; C22; C22B; C22B3/00; C22B3/20; C22B3/22; C22B3/24; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
A CYCLIC PROCESS FOR REGENERATNG ACTIVATED CARBON LOADED WITH ADSORBED GOLD WHILE RECOVERING THE SAME, WHICH COMPRISES FIRST TREATING SUCH CARBON WITH A CAUSTIC SOLUTION OF SODIUM SULFIDE TO EXTRACT THE GOLD THEREFROM, SEPARATING THE THUS-REGENERATED ACTIVE CARBON, STRIPPING THE GOLD FROM THE PREGNANT CAUSTIC SODIUM SULFIDE SOLUTION BY ELECTROLYSIS BETWEEN AN INSOLUBLE ANODE AND A PRE-COATED CHARRED EXCELSIOR CATHODE, RRECOVERING THE DEPOSITED GOLD, THEN ADDING SODIUM SULFITE TO REACT WITH THE FORMED POLYSULFIDE TO REGENERATE THE CAUSTIC SODIUM SULFIDE SOLUTION FOR REUSE IN THE PROCESS, SAID CATHODE HAVING BEEN PRE-COATED BY ELECTRODEPOSITING GOLD THEREIN FROM A CYANIDE SOLUTION.
Claim 2
Dependent Claim
99 words
A CYCLIC PROCESS FOR REGENERATNG ACTIVATED CARBON LOADED WITH ADSORBED GOLD WHILE RECOVERING THE SAME, WHICH COMPRISES FIRST TREATING SUCH CARBON WITH A CAUSTIC SOLUTION OF SODIUM SULFIDE TO EXTRACT THE GOLD THEREFROM, SEPARATING THE THUS-REGENERATED ACTIVE CARBON, STRIPPING THE GOLD FROM THE PREGNANT CAUSTIC SODIUM SULFIDE SOLUTION BY ELECTROLYSIS BETWEEN AN INSOLUBLE ANODE AND A PRE-COATED CHARRED EXCELSIOR CATHODE, RRECOVERING THE DEPOSITED GOLD, THEN ADDING SODIUM SULFITE TO REACT WITH THE FORMED POLYSULFIDE TO REGENERATE THE CAUSTIC SODIUM SULFIDE SOLUTION FOR REUSE IN THE PROCESS, SAID CATHODE HAVING BEEN PRE-COATED BY ELECTRODEPOSITING GOLD THEREIN FROM A CYANIDE SOLUTION.
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) | 1954-12-24 | 1955-06-25 | 1955-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-24 | 1959-06-25 | 1959-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-24 | 1963-06-25 | 1963-12-25 | $7700.00 | Window Closed / Lapsed |