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EP0010367A1
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EP
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Method of recovering metal values
Assignee: Anglo American Corp of South Africa Pty Ltd
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Filing: 1979-09-25
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Granted: —
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Expires: 1999-09-25
Abstract
Abstract A method of recovering metal values selected from gold, silver, copper and nickel from an activated carbon support having one or more of these values adsorbed thereon in the form of an alkaline eartn metal ionic complex, the metal value forming part of the anionic portion thereof, including the steps of contacting the support with a pre-treatment reagent, followed by desorbing the metal values from the support with water having a low concentration of metal cations such as deionised water, the method being characterised by the pre-treatment reagent which is a mixture of an organic solvent such as an alcohol or a ketone and an alkali metal cyanide or hydroxide solution.
Inventors
- 👤 Raymond John Davidson
- 👤 Vittorio Veronese
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 22:26
CPC Classifications
C; C22; C22B; C22B3/00; C22B3/20; C22B3/44; C22B3/22; C22B3/24; C22B3/26; C22B3/262; C22B3/306; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
112 words
A method of recovering metal values selected from gold, silver, copper and nickel from a carbon support having one or more of these values adsorbed thereon in the form of an alkaline earth metal ionic complex, the metal value forming part of the anionic portion thereof, including the steps of contacting the support with a pre-treatment reagent, followed by desorbing the metal values from the support with water having a low concentration of metal cations characterised in that the pre-treatment reagent is a mixture of:- (a) an organic solvent, and (b) a solution selected from the group of an alkali metal cyanide solution, an alkali metal hydroxide solution and a mixture thereof.
Claim 2
Independent Claim
112 words
A method of recovering metal values selected from gold, silver, copper and nickel from a carbon support having one or more of these values adsorbed thereon in the form of an alkaline earth metal ionic complex, the metal value forming part of the anionic portion thereof, including the steps of contacting the support with a pre-treatment reagent, followed by desorbing the metal values from the support with water having a low concentration of metal cations characterised in that the pre-treatment reagent is a mixture of:- (a) an organic solvent, and (b) a solution selected from the group of an alkali metal cyanide solution, an alkali metal hydroxide solution and a mixture thereof.
Claim 3
Dependent Claim
25 words
A method according to claim 1 wherein the organic solvent is present in the mixture in an amount of 1 to 10 percent by volume.
Claim 4
Dependent Claim
23 words
A method according to claim 1 wherein the organic solvent is present in the mixture in an amount of 5 percent by volume.
Claim 5
Independent Claim
20 words
A method according to any one of the preceding claims wherein the organic solvent is an alcohol or a ketone.
Claim 6
Dependent Claim
17 words
A method according to claim 4 wherein the alcohol is isopropyl alcohol or the ketone is acetone.
Claim 7
Independent Claim
45 words
A method according to any one of the preceding claims wherein the solution contains an alkali metal cyanide of concentration in the range 1 to 10 percent by weight and an alkali metal hydroxide of concentration in the range 0,1 to 20 percent by weight.
Claim 8
Independent Claim
28 words
A method according to any one of claims 1 to 5 wherein the solution is an alkali metal hydroxide solution of concentration 0,1 to 20 percent by weight.
Claim 9
Independent Claim
17 words
A method according to any one of the preceding claims wherein the carbon support is activated carbon.
Claim 10
Independent Claim
27 words
A method according to any one of the preceding claims wherein the water having a low concentration of metal cations is deionised, distilled or otherwise softened water.
References Cited (Backward Citations)
US3970737A
Cited
DE2731029A1
Cited
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