US4026772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct electrochemical recovery of copper from dilute acidic solutions
Assignee: Kennecott Utah Copper LLC
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Filing: 1975-07-16
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Granted: 1977-05-31
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Expires: 1995-07-16
Abstract
Abstract Recovery of copper and/or other metal values from pregnant, highly dilute liquors and conversion of the barren liquor to a suitable lixiviant; for recovery of copper or other metal values from leaching systems, such as acid treatment of mine waste dumps, vat or heap leaching and insitu mining as part of an overall copper recovery process.
Inventors
- 👤 Paul R. Ammann
- 👤 Glenn M. Cook
- 👤 Charles Portal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:13
CPC Classifications
C; C25; C25C; C25C1/00; C25C1/12; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
162 words
In a process for recovering copper from dilute solution of pregnant liquor from a copper leaching system, the steps comprising: (a) maintaining the pH value of said liquor equal to or more acid than a barren leach solution, said liquor comprising from about 0.1 to about 20.0 gpl copper and up to about 10.0 gpl iron as ferrous iron and up to about 10.0 gpl iron as ferric iron, including incidental impurities and solvated metals associated with copper; (b) introducing said liquor into an electrolysis cell having a cathode of an electrically conductive porous material and an anode; (c) applying a current such that the current density in said cathode is from about 3 to 100 amps per square foot of cross-section; (d) flowing said liquor through said electrolysis cell at a rate whereby substantially all copper in said liquor is recovered on said cathodic material; and (e) recovering said copper from a cathode product comprised of copper and said cathodic material.
Claim 2
Dependent Claim
162 words
In a process for recovering copper from dilute solution of pregnant liquor from a copper leaching system, the steps comprising: (a) maintaining the pH value of said liquor equal to or more acid than a barren leach solution, said liquor comprising from about 0.1 to about 20.0 gpl copper and up to about 10.0 gpl iron as ferrous iron and up to about 10.0 gpl iron as ferric iron, including incidental impurities and solvated metals associated with copper; (b) introducing said liquor into an electrolysis cell having a cathode of an electrically conductive porous material and an anode; (c) applying a current such that the current density in said cathode is from about 3 to 100 amps per square foot of cross-section; (d) flowing said liquor through said electrolysis cell at a rate whereby substantially all copper in said liquor is recovered on said cathodic material; and (e) recovering said copper from a cathode product comprised of copper and said cathodic material.
Claim 3
Dependent Claim
25 words
The process as defined in claim 1 and wherein the cathode material is a coke material of minus 20 to plus 80 mesh sieve size.
Claim 4
Dependent Claim
23 words
The process as defined in claim 2 and wherein less than 25% of coke from the cathode is used for refining said copper.
Claim 5
Dependent Claim
26 words
The process as defined in claim 1 and wherein in step (b) said liquor flows first through said cathode and then by or through said anode.
Claim 6
Dependent Claim
26 words
The process as defined in claim 1 and wherein in step (b) said liquor flows first through or by said anode and then through said cathode.
Claim 7
Dependent Claim
45 words
The process as defined in claim 1 and wherein the pregnant liquor introduced into said electrolysis cell has added thereto an acid to adjust the pH value to less than about 2.2 to increase the liquor conductivity and to maintain solubility of reactants and products.
Claim 8
Dependent Claim
26 words
The process as defined in claim 1 and wherein the recovering of copper is from said cathode product by melting and refining treatment of said copper.
Claim 9
Dependent Claim
60 words
The process as defined in claim 1 and wherein the cathode product from the electrolysis cell is classified before introduction into a furnace zone and the fines thereof admixed with a make-up, electrically conductive porous material, for forming a slurry of a particle size between 1/2 inch to 100 mesh sieve size, suitable for introduction in said electrolysis cell. 28
Claim 10
Dependent Claim
18 words
The process as defined in claim 1 wherein the copper is recovered from said cathode product by electrorefining.
Claim 11
Dependent Claim
21 words
The process as defined in claim 1 wherein said electrically conductive material is of sieve size between +4 to +260 mesh.
Claim 12
Dependent Claim
33 words
The process as defined in claim 1 and wherein the cathode material is of a porosity from about 25 to about 97% at the outset of the electrolytic reaction of said pregnant liquor.
Claim 13
Dependent Claim
15 words
The process as defined in claim 1 and wherein copper of 99.8% purity is produced.
Claim 14
Dependent Claim
41 words
The process as defined in claim 1 and wherein reprocessed coke with an average copper content of about 2% is returned as a slurry to a cathode as an electrically conductive porous material for said electrolysis cell for forming said cathode.
Claim 15
Dependent Claim
29 words
The process as defined in claim 1 and wherein the pregnant liquor velocity through said cathode is from about 0.0006 to 5.0 gallons per minute/ft 2 of cathode face.
Claim 16
Dependent Claim
28 words
The process as defined in claim 1 and wherein the liquid flows through the cell once, before it is reconstituted as a barren leaching liquid depleted in copper.
Claim 17
Dependent Claim
34 words
The process as defined in claim 1 and wherein a barren leach solution is returned as a regenerated lixiviant to the copper leaching system lower in ferrous iron as compared to the pregnant liquor.
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) | 1980-05-30 | 1980-11-29 | 1981-05-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-30 | 1984-11-29 | 1985-05-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-30 | 1988-11-29 | 1989-05-31 | $7700.00 | Window Closed / Lapsed |