US4214955A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrolytic purification of metals
Assignee: Alcoa Corp
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Filing: 1979-01-02
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Granted: 1980-07-29
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Expires: 1999-01-02
Abstract
Abstract A method of electrolytically separating metal from impurities comprises providing the metal and impurities in a molten state in a container having a porous membrane therein, the membrane having a porosity greater than 48%, being capable of containing the molten metal in the container, and being permeable by a molten electrolyte. The metal is electrolytically transferred through the membrane to a cathode in the presence of the electrolyte for purposes of separating or removing impurities from the metal.
Inventors
- 👤 Kenneth A. Bowman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:48
CPC Classifications
C; C25; C25C; C25C3/00; C25C3/06; C25C3/24
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
83 words
A method of electrolytically removing impurities from metal comprising the steps of: (a) providing a metal containing impurities in a molten state in a container having a porous membrane therein, the membrane having a porosity greater than 50% and up to about 97% and being capable of containing the molten metal and being permeable by a molten electrolyte; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte thereby substantially removing the impurities from the metal.
Claim 2
Independent Claim
83 words
A method of electrolytically removing impurities from metal comprising the steps of: (a) providing a metal containing impurities in a molten state in a container having a porous membrane therein, the membrane having a porosity greater than 50% and up to about 97% and being capable of containing the molten metal and being permeable by a molten electrolyte; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte thereby substantially removing the impurities from the metal.
Claim 3
Dependent Claim
15 words
The process according to claim 1 wherein porous carbon is employed as the porous wall.
Claim 4
Dependent Claim
52 words
The process according to claim 1 wherein said electrolyte employed comprises at least one salt selected from the group consisting of metal fluoride and metal chloride of the metal to be electrolytically transferred and at least one salt selected from the group consisting of aluminum, sodium, potassium, lithium, calcium and magnesium halide.
Claim 5
Dependent Claim
11 words
The process according to claim 1 wherein the metal is aluminum.
Claim 6
Dependent Claim
44 words
The process according to claim 4 wherein said electrolyte employed comprises at least one salt selected from the group consisting of aluminum fluoride and aluminum chloride and at least one salt selected from the group consisting of sodium, potassium, lithium, calcium and magnesium chloride.
Claim 7
Dependent Claim
23 words
The process according to claim 1 wherein the electrolyte comprises 5 to 99 wt.% LiCl and 1 to 25 wt.% AlCl 3 .
Claim 8
Dependent Claim
21 words
The process according to claim 1 wherein the electrolyte has a temperature in the range of 675° C. to 925° C.
Claim 9
Dependent Claim
24 words
The process according to claim 1 wherein molten aluminum is capable of being electrolytically transferred at a current density of 1382 amps/ft 2 .
Claim 10
Independent Claim
129 words
A method of electrolytically purifying aluminum alloy comprising the steps of: (a) providing a metal and impurities in a container having a porous carbon membrane therein, the membrane having a porosity in the range greater than 50% and up to about 97% and being capable of containing the molten metal and being permeable by a molten electrolyte containing at least one salt selected from the group consisting of aluminum fluoride and aluminum chloride and at least one salt selected from the group consisting of sodium, potassium, lithium, manganese and magnesium halide; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte at a temperature in the range of 675° to 925° C. thereby purifying said aluminum by separating it from alloying constituents.
Claim 11
Independent Claim
129 words
A method of electrolytically purifying aluminum alloy comprising the steps of: (a) providing a metal and impurities in a container having a porous carbon membrane therein, the membrane having a porosity in the range greater than 50% and up to about 97% and being capable of containing the molten metal and being permeable by a molten electrolyte containing at least one salt selected from the group consisting of aluminum fluoride and aluminum chloride and at least one salt selected from the group consisting of sodium, potassium, lithium, manganese and magnesium halide; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte at a temperature in the range of 675° to 925° C. thereby purifying said aluminum by separating it from alloying constituents.
Claim 12
Independent Claim
83 words
A method of electrolytically removing impurities from metal comprising the steps of: (a) providing a metal containing impurities in a molten state in a container having a porous membrane therein, the membrane having a porosity in the range of about 70% to 97% and being capable of containing the molten metal and being permeable by a molten electrolyte; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte thereby substantially removing the impurities from the metal.
Claim 13
Independent Claim
83 words
A method of electrolytically removing impurities from metal comprising the steps of: (a) providing a metal containing impurities in a molten state in a container having a porous membrane therein, the membrane having a porosity in the range of about 70% to 97% and being capable of containing the molten metal and being permeable by a molten electrolyte; and (b) electrolytically transferring metal through said membrane to a cathode in the presence of the electrolyte thereby substantially removing the impurities from the metal.
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) | 1983-07-29 | 1984-01-28 | 1984-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-29 | 1988-01-28 | 1988-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-29 | 1992-01-28 | 1992-07-29 | $7700.00 | Window Closed / Lapsed |