US4198231A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery and separation of gadolinium and gallium
Assignee: Rio Tinto Alcan Inc
•
Filing: 1979-02-05
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Granted: 1980-04-15
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Expires: 1999-02-05
Abstract
Abstract Gallium and gadolinium are recovered and separated from scrap material of substances which contain both of these elements in the form of oxides or compounds which can be transformed to the oxides. The scrap is finely ground and then dissolved in a strong, aqueous mineral acid. The gadolinium is precipitated from the purified solution as the oxalate; then the gallium is deposited in the metallic form by means of electrolysis. The electrolytic deposition of the gallium can also take place before the gadolinium is precipitated out as the oxalate.
Inventors
- 👤 Erwin Gusset
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:13
CPC Classifications
C; C22; C22B; C22B59/00; C22B58/00; C22B7/00; C22B7/006; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
A process for the recovery and separation of gadolinium and gallium from scrap material of substances containing both of these elements basically in the form of oxides or compounds which can be transformed to the oxides including the steps of (a) grinding the scrap material to a particle size smaller than 100 μm, (b) dissolving the finely ground scrap in a strong, aqueous mineral acid, (c) precipitating out impurities, (d) precipitating the gadolinium as the oxalate, and (e) depositing the gallium in the metallic form by electrolysis.
Claim 2
Dependent Claim
87 words
A process for the recovery and separation of gadolinium and gallium from scrap material of substances containing both of these elements basically in the form of oxides or compounds which can be transformed to the oxides including the steps of (a) grinding the scrap material to a particle size smaller than 100 μm, (b) dissolving the finely ground scrap in a strong, aqueous mineral acid, (c) precipitating out impurities, (d) precipitating the gadolinium as the oxalate, and (e) depositing the gallium in the metallic form by electrolysis.
Claim 3
Dependent Claim
27 words
A process according to claim 1 in which the starting material is given a thermal treatment at a temperature of at least 400° C. before being ground.
Claim 4
Dependent Claim
22 words
A process according to claim 1 in which the starting material is ground to a particle size of less than 40 μm.
Claim 5
Dependent Claim
19 words
A process according to claim 1 in which the finely ground starting material is dissolved in concentrated hydrochloric acid.
Claim 6
Dependent Claim
26 words
A process according to claim 1 in which the purification step (c) of the solution takes place by cementation of the more noble metals as gallium.
Claim 7
Dependent Claim
26 words
A process according to claim 5 in which the cementation is carried out by dispersing fine droplets of metallic gallium in the solution to be purified.
Claim 8
Dependent Claim
24 words
A process according to claim 1 in which the purification step (c) of the solution is carried out by precipitation of impurities as sulphides.
Claim 9
Dependent Claim
43 words
A process according to claim 1 in which the precipitation of gadolinium oxalate is carried out at a pH of 0.5-1.2, and wherein a quantity of oxalic acid is employed in an amount 1.5-3.5 times the stoichiometric amount of gadolinium in the solution.
Claim 10
Dependent Claim
29 words
A process according to claim 1 in which the gallium is deposited electrolytically in a basic medium with a high chloride ion content after the precipitation of gadolinium oxalate.
Claim 11
Dependent Claim
85 words
A process for the recovery and separation of gadolinium and gallium from scrap material of substances containing both of these elements basically in the form of oxides or compounds which can be transformed to oxides including the steps of (a) grinding the scrap material to a particle size smaller than 100 μm, (b) dissolving the finely ground material in a strong, aqueous mineral acid, (c) precipitating out impurities, (d) depositing the gallium electrolytically in the metallic form, and (e) precipitating the gadolinium as the oxalate.
Claim 12
Dependent Claim
85 words
A process for the recovery and separation of gadolinium and gallium from scrap material of substances containing both of these elements basically in the form of oxides or compounds which can be transformed to oxides including the steps of (a) grinding the scrap material to a particle size smaller than 100 μm, (b) dissolving the finely ground material in a strong, aqueous mineral acid, (c) precipitating out impurities, (d) depositing the gallium electrolytically in the metallic form, and (e) precipitating the gadolinium as the oxalate.
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) | 1983-04-15 | 1983-10-15 | 1984-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-04-15 | 1987-10-15 | 1988-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-04-15 | 1991-10-15 | 1992-04-15 | $7700.00 | Window Closed / Lapsed |