Patent US4072508A successfully refreshed from Google Patents.
US4072508A
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Method for recovering palladium from spent palladium catalysts
Assignee: University of Chemistry and Technology
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Filing: 1976-12-17
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Granted: 1978-02-07
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Expires: 1996-12-17
Abstract
Abstract A technique for recovering palladium from a spent palladium catalyst or ash thereof involves fluorinating the catalyst or ash at elevated temperatures to yield palladium fluoride and decomposing the fluoride with a mineral acid at a temperature ranging from 90° - 100° C.
Inventors
- 👤 Ludek Vodicka
- 👤 Ivo Peka
- 👤 Voktor Suchy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 12:38
CPC Classifications
C; C01; C01G; C01G55/00; C01G55/005; C22; C22B; C22B11/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
60 words
A method for recovering palladium values from spent palladium catalysts and ash thereof which comprises the steps of fluorinating the spent catalyst and ash at a temperature which increases gradually from 200° - 500° C and decomposing palladium fluorides so obtained with a mineral acid at a temperature ranging from 90° - 100° C to obtain palladium values in solution.
Claim 2
Independent Claim
60 words
A method for recovering palladium values from spent palladium catalysts and ash thereof which comprises the steps of fluorinating the spent catalyst and ash at a temperature which increases gradually from 200° - 500° C and decomposing palladium fluorides so obtained with a mineral acid at a temperature ranging from 90° - 100° C to obtain palladium values in solution.
Claim 3
Dependent Claim
13 words
Method in accordance with claim 1, wherein fluorination is effected with elemental fluorine.
Claim 4
Dependent Claim
18 words
Method in accordance with claim 1, wherein fluorination is effected with a mixture of fluorine and hydrogen fluoride.
Claim 5
Dependent Claim
13 words
Method in accordance with claim 1, wherein the mineral acid is hydrochloric acid.
Claim 6
Dependent Claim
13 words
Method in accordance with claim 3, wherein the mineral acid is hydrochloric acid.
References Cited (Backward Citations)
US3969267A
Cited
US3958985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-06 | 1981-08-08 | 1982-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-06 | 1985-08-08 | 1986-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-06 | 1989-08-08 | 1990-02-07 | $7700.00 | Window Closed / Lapsed |