Patent US3976475A successfully refreshed from Google Patents.
US3976475A
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Process for the recovery of tantalum and/or niobium from acid solutions thereof
Assignee: MARKLAND SVEND AAGE
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Filing: 1975-08-20
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Granted: 1976-08-24
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Expires: 1995-08-20
Abstract
Abstract The invention is concerned with the recovery and separation of tantalum and/or niobium from a solution of these elements in aqueous mineral acid, preferably sulfuric acid. The element or elements is/are extracted from the acid solution thereof by means of an amine, preferably a tertiary, long-chained alkyl amine, in the presence of hydrogen peroxide and of fluoride ions. Thereby the extraction and separation can be performed effectively at comparatively low acid concentration, normally below a concentration of 4N.
Inventors
- 👤 Svend Aage Markland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 15:45
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/20; C22B34/24; C01; C01G; C01G33/00; C01G35/00; C01G35/003; C22B3/00; C22B3/20; C22B3/26; C22B3/28; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
93 words
A process for the recovery of at least one of the metals tantalum and niobium from an aqueous mineral acid-containing, preferably sulfuric acid-containing, solution containing such metals, by extraction in at least one step by means of an amine, preferably an amine selected from secondary and tertiary, long-chained alkyl amines, in the presence of hydrogen peroxide, and isolating the metal from the organic extract, said process being characterized by the fact that the extraction of the acid, hydrogen peroxide-containing solution by means of an amine is performed in the presence of fluoride ions.
Claim 2
Dependent Claim
93 words
A process for the recovery of at least one of the metals tantalum and niobium from an aqueous mineral acid-containing, preferably sulfuric acid-containing, solution containing such metals, by extraction in at least one step by means of an amine, preferably an amine selected from secondary and tertiary, long-chained alkyl amines, in the presence of hydrogen peroxide, and isolating the metal from the organic extract, said process being characterized by the fact that the extraction of the acid, hydrogen peroxide-containing solution by means of an amine is performed in the presence of fluoride ions.
Claim 3
Dependent Claim
32 words
A process as claimed in claim 1 characterized in that the acid concentration in the solution to be extracted is kept below 10N and preferably in the range from 0.2N to 4N.
Claim 4
Dependent Claim
26 words
A process as claimed in claim 2 characterized in that the concentration of acid in the solution is kept in the range from 0.4N to 2N.
Claim 5
Dependent Claim
56 words
A process as claimed in claim 1 characterized in that the proportion of hydrogen peroxide incorporated into thesolution to be extracted is at least approximately equal to the proportion which will be necessary for the conversion of Ta- and Nb-compounds present into complexes containing one molecule of H 2 O 2 for each Ta- and Nb-atom.
Claim 6
Dependent Claim
50 words
A process as claimed in claim 1 characterized in that a proportion of fluoride ions is incorporated into the solution to be extracted, which does not substantially exceed the proportion, at which -- at the extraction conditions used -- a maximum extraction of tantalum as well as niobium is otained.
Claim 7
Dependent Claim
37 words
A process as claimed in claim 1 characterized in that a concentration of fluoride ions is used, at which a substantially maximum extraction of tantalum is obtained simultaneously with a substantially less than maximum extraction of niobium.
Claim 8
Dependent Claim
28 words
A process as claimed in claim 1 characterized in that the fluoride ions are incorporated in the form of a salt soluble in the solution to be extracted.
Claim 9
Dependent Claim
27 words
A process as claimed in claim 7 characterized in that the said salt is selected from the group consisting of ammonium fluoride, potassium fluoride and sodium fluoride.
References Cited (Backward Citations)
US3051547A
Cited
US2927855A
Cited
US2950966A
Cited
US2953453A
Cited
US3117833A
Cited
US3065046A
Cited
US3712939A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-24 | 1980-02-23 | 1980-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-24 | 1984-02-23 | 1984-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-24 | 1988-02-23 | 1988-08-24 | $7700.00 | Window Closed / Lapsed |