US3970737A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal, particularly gold, recovery from adsorbed cyanide complexes
Assignee: Crucible SA
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Filing: 1974-10-29
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Granted: 1976-07-20
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Expires: 1994-10-29
Abstract
Abstract The invention provides a method of recovering transition or noble metal values, particularly gold and silver values, from a support having absorbed thereon the metal values in the form of an ionic complex, particularly a cyanide ionic complex, by desorbing the metal values with water of low cation concentration such as deionized or softened water. When the cation of the complex is an alkaline earth metal cation then the support is preferably subjected to a pre-treatment with an alkali metal salt solution to effect an exchange reaction before the desorption step.
Inventors
- 👤 Raymond John Davidson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:07
CPC Classifications
C; C01; C01G; C01G55/00; C01G55/001; B; B01; B01D; B01D15/00; C01G5/00; C01G5/003; C01G7/00; C01G7/003; C22; C22B; C22B3/00; C22B3/20; C22B3/22; C22B3/24; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
86 words
A method of recovering metal values selected from gold, silver, copper and nickel from a support having adsorbed thereon the metal values in the form of a cyanide ionic complex, the metal values forming part of the anionic portion thereof, including the step of contacting the support with water of low metal cation concentration to desorb the metal values, the cation of the complex being an alkaline earth metal cation and the support being contacted with an alkali metal salt solution prior to the desorption step.
Claim 2
Independent Claim
86 words
A method of recovering metal values selected from gold, silver, copper and nickel from a support having adsorbed thereon the metal values in the form of a cyanide ionic complex, the metal values forming part of the anionic portion thereof, including the step of contacting the support with water of low metal cation concentration to desorb the metal values, the cation of the complex being an alkaline earth metal cation and the support being contacted with an alkali metal salt solution prior to the desorption step.
Claim 3
Dependent Claim
22 words
A method according to claim 1, wherein the alkali metal salt solution is selected from a sodium, potassium and lithium salt solution.
Claim 4
Dependent Claim
31 words
A method according to claim 1, wherein the anion of the alkali metal salt solution is one which forms an insoluble or substantially insoluble salt with the alkaline earth metal cation.
Claim 5
Dependent Claim
22 words
A method according to claim 1, wherein the alkali metal salt solution is selected from a sodium, potassium and lithium carbonate solution.
Claim 6
Dependent Claim
16 words
A method according to claim 1, wherein the alkali metal salt solution has a basic pH.
Claim 7
Dependent Claim
22 words
A method according to claim 1, wherein the alkali metal salt solution is a potassium carbonate/potassium hydroxide solution having a basic pH.
Claim 8
Dependent Claim
14 words
A method according to claim 1, wherein the water is deionized or softened water.
Claim 9
Independent Claim
77 words
A method of recovering gold or silver values from a support having adsorbed thereon the metal values in the form of an alkaline earth metal cyanide ionic complex including the steps of contacting the support with alkali metal salt solution, the anion of the salt being capable of forming an insoluble or substantially insoluble salt with the alkaline earth metal of the complex, and desorbing the metal values from the support with water of low cation concentration.
Claim 10
Independent Claim
77 words
A method of recovering gold or silver values from a support having adsorbed thereon the metal values in the form of an alkaline earth metal cyanide ionic complex including the steps of contacting the support with alkali metal salt solution, the anion of the salt being capable of forming an insoluble or substantially insoluble salt with the alkaline earth metal of the complex, and desorbing the metal values from the support with water of low cation concentration.
Claim 11
Dependent Claim
26 words
A method according to claim 8, wherein the alkali metal salt solution is selected from a potassium, sodium and lithium carbonate solution having a basic pH.
Claim 12
Dependent Claim
14 words
A method according to claim 9, wherein the water is deionized or softened water.
Claim 13
Dependent Claim
14 words
A method according to claim 8, wherein the water is deionized or softened water.
References Cited (Backward Citations)
US2965441A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-20 | 1980-01-19 | 1980-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-20 | 1984-01-19 | 1984-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-20 | 1988-01-19 | 1988-07-20 | $7700.00 | Window Closed / Lapsed |