Patent US3856912A successfully refreshed from Google Patents.
US3856912A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of platinum from deactivated catalysts
Assignee: Universal Oil Products Co
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Filing: 1973-05-03
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Granted: 1974-12-24
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Expires: 1993-05-03
Abstract
Abstract Trace amounts of platinum, otherwise lost, are recovered from the alum solution resulting from the digestion of spent aluminabased platinum catalyst in sulfuric acid. The alum solution is commingled with a normally liquid trialkyl phosphate and a platinum-containing residue forms at the interface of said liquids as they are allowed to settle out into an upper and lower liquid phase.
Inventors
- 👤 K Vesely
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:35
CPC Classifications
C; C01; C01G; C01G55/00; C01G55/001; C22; C22B; C22B3/00; C22B3/20; C22B3/26; C22B3/38; C22B3/384; C22B3/3846; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
126 words
A METHOD FOR THE RECOVERY OF PLATINUM FORM A DEACTIVATED CATALYST COMPOSITE COMPRISING PLATINUM ON AN ALUMINA SUPPORT, WHICH COMPRISES THE STEPS OF DIGESTING SAID COMPOSITE IN SULFURIC ACID TO DISSOLVE THE ALUMINA, SEPARATING THE RESULTANT ALUMINUM SULFATE SOLUTION FROM THE UNDISSOLVED PLATINUMCONTAINING RESIDUE, COMMINGLING SAID SOLUTION WITH A LIQUID TRIALKYL PHOSPHATE HAVING FROM ONE TO FIVE CARBON ATOMS IN EACH OF THE ALKYL GROUPS, MAINTAINING THE RESULTANT MIXTURE AT QUIESCENT CONDITIONS TO SEPARATE THE SAME INTO UPPER AND LOWER LIQUID LAYERS WITH A PLATINUM-CONTAINING RESIDUE AT THE INTERFACE, WITHDRAWING THE LAST-MENTIONED RESIDUE AND COMBINING THE SAME WITH SAID UNDISSOLVED PLATINUM-CONTAINING RESIDUE FROM THE DIGESTIBLE STEP, DIGESTING THE COMBINED RESODUES WITH AQUA REGIA TO DISSOLVE THE PLATINUM AND FROM CHLOROPLANTINIC ACID, AND RECOVERING SAID CHLOROPLATINIC ACID.
Claim 2
Independent Claim
126 words
A METHOD FOR THE RECOVERY OF PLATINUM FORM A DEACTIVATED CATALYST COMPOSITE COMPRISING PLATINUM ON AN ALUMINA SUPPORT, WHICH COMPRISES THE STEPS OF DIGESTING SAID COMPOSITE IN SULFURIC ACID TO DISSOLVE THE ALUMINA, SEPARATING THE RESULTANT ALUMINUM SULFATE SOLUTION FROM THE UNDISSOLVED PLATINUMCONTAINING RESIDUE, COMMINGLING SAID SOLUTION WITH A LIQUID TRIALKYL PHOSPHATE HAVING FROM ONE TO FIVE CARBON ATOMS IN EACH OF THE ALKYL GROUPS, MAINTAINING THE RESULTANT MIXTURE AT QUIESCENT CONDITIONS TO SEPARATE THE SAME INTO UPPER AND LOWER LIQUID LAYERS WITH A PLATINUM-CONTAINING RESIDUE AT THE INTERFACE, WITHDRAWING THE LAST-MENTIONED RESIDUE AND COMBINING THE SAME WITH SAID UNDISSOLVED PLATINUM-CONTAINING RESIDUE FROM THE DIGESTIBLE STEP, DIGESTING THE COMBINED RESODUES WITH AQUA REGIA TO DISSOLVE THE PLATINUM AND FROM CHLOROPLANTINIC ACID, AND RECOVERING SAID CHLOROPLATINIC ACID.
Claim 3
Dependent Claim
15 words
The method of claim 1 further characterized in that said trialkyl phosphate is tributyl phosphate.
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) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |