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Patent US3271135A successfully refreshed from Google Patents.
US3271135A
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US
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Gold recovery process using an alkali metal hydrosulfite with a water soluble oxygen containing compound
Assignee: Individual
•
Filing: 1963-12-26
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Granted: 1966-09-06
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Expires: 1983-12-26
Abstract
No abstract record available.
Inventors
- 👤 Davidoff Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 16:46
CPC Classifications
C; C01; C01G; C01G7/00; C01G7/003; C22; C22B; C22B3/00; C22B3/20; C22B3/26; C22B3/28; C22B11/00; C22B11/08; C22B3/306; C22B3/32; C22B3/34; C22B3/40; C22B3/402; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
102 words
A METHOD OF RECOVERING GOLD FROM AN AQUEOUS SOLUTION OF ALKALI METAL GOLD CYANIDE CONSISTING ESSENTIALLY IN ADDING TO THE SOLUTION ALKALI METAL HYDROSULFITE AND AT LEAST ONE MEMBER SELECTED FROM THE GROUP WATER SOLUBLE OXYGEN-CONTAINING COMPOUNDS CONSISTING OF ALDEHYDES, HYDROXYL-CONTAINING AMINES, AMMONIUM AND ALKALI METAL PHOSPHATES, HYPOPHOSPHITES AND THIOSULFATES, AND AMINO- AND HYDROXY-CARBOXYLIC ACIDS AND THEIR AMMONIUM AND ALKALI METAL SALTS IN A COMBINED MOLAR AMOUNT AT LEAST EQUIVALENT TO THE GOLD IN SAID SOLUTION, MAINTAINING THE RESULTING SOLUTION AT AN ELEVATED TEMPERATURE ABOVE ABOUT 150*F. UNTIL CESSATION OF PRECIPITATION OF THE GOLD, AND REMOVING THE PRECIPITATED GOLD FROM THE SOLUTION.
Claim 2
Independent Claim
102 words
A METHOD OF RECOVERING GOLD FROM AN AQUEOUS SOLUTION OF ALKALI METAL GOLD CYANIDE CONSISTING ESSENTIALLY IN ADDING TO THE SOLUTION ALKALI METAL HYDROSULFITE AND AT LEAST ONE MEMBER SELECTED FROM THE GROUP WATER SOLUBLE OXYGEN-CONTAINING COMPOUNDS CONSISTING OF ALDEHYDES, HYDROXYL-CONTAINING AMINES, AMMONIUM AND ALKALI METAL PHOSPHATES, HYPOPHOSPHITES AND THIOSULFATES, AND AMINO- AND HYDROXY-CARBOXYLIC ACIDS AND THEIR AMMONIUM AND ALKALI METAL SALTS IN A COMBINED MOLAR AMOUNT AT LEAST EQUIVALENT TO THE GOLD IN SAID SOLUTION, MAINTAINING THE RESULTING SOLUTION AT AN ELEVATED TEMPERATURE ABOVE ABOUT 150*F. UNTIL CESSATION OF PRECIPITATION OF THE GOLD, AND REMOVING THE PRECIPITATED GOLD FROM THE 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) | 1969-09-05 | 1970-03-07 | 1970-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-05 | 1974-03-07 | 1974-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-05 | 1978-03-07 | 1978-09-06 | $7700.00 | Window Closed / Lapsed |