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US 4,543,169 AGranted
Gold recovery process
AssigneeRAI Research Corporation
InventorsVincent F. D'Agostino, Joseph Y. Lee, Stephen Zapisek, George Schore
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Abstract
A method is described for precious metal recovery from acidic precious metal-cyanide solutions by means of a weakly-basic anion-exchange material comprising a polymeric felt incorporating radiation-grafted pyridinyl functional groups.
Claims16
A method of metal recovery comprising;
- (a) forming a weakly-basic anion-exchange material by radiation-grafting monomers comprising pyridinyl functional groups to a polymeric felt substrate to the extent of 10-1500%;
- and
- (b) contacting the anion-exchange material with an acidic aqueous solution comprising metal-cyanide anions so as to form a complex between the anions and the pyridinyl groups, thereby removing the anions from solution.
A method of gold recovery comprising:
- (a) forming a weakly-basic anion-exchange material by radiation-grafting 2-vinyl pyridine or 4-vinyl pyridine to a polymeric felt substrate to the extent of 100-1000%;
- and
- (b) contacting the resin with an acidic aqueous solution comprising potassium gold dicyanide so as to form a complex between the pyridine groups and the gold dicyanide anions, thereby removing the anions from solution.
A method of precious metal recovery comprising:
- contacting a weakly basic anionic exchange material with an acidic aqueous solution comprising metal-cyanide anions so as to form a complex between the anions and the material, thereby removing the anions from the solution;
- said material comprising a polymeric felt substrate radiation-grafted to the extent of 10-1500% with a monomer comprising a pyridinyl functional group.
Dependencies are inferred from the claim text.