Extraction process for the recovery of tungsten from low level sources
AssigneeGTE Laboratories Incorporated
InventorsSamuel Natansohn, Sophia R. Su
Life of this patent
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Abstract
A process for recovering tungsten from low level sources such as naturally occurring brines in a form substantially free of contaminating boron comprises adjusting the pH of the source solution to a value below about pH 8, contacting the pH-adjusted solution with an ion exchange resin, preferentially eluting the tungsten values in an aqueous eluate, extracting the eluate solution with an organic extractant comprising o-mercaptobenzoic acid, a quaternary alkylammonium salt and an inert organic solvent, and stripping the tungsten-loaded organic extractant solution with an aqueous basic stripping solution.
Claims13
A process for recovering tungsten substantially free of contaminating boron from aqueous media containing tungsten and boron comprising the steps of:
- (a) adjusting the pH of said aqueous medium to a value below about pH 8;
- (b) contacting the pH-adjusted aqueous medium with an ion exchange resin to load the resin with tungsten and boron values from said aqueous medium;
- (c) eluting the loaded resin with an aqueous eluant solution to selectively recover a portion of the tungsten from said loaded resin;
- (d) adjusting the pH of the tungsten-containing aqueous eluate solution to a value below about pH 3;
- (e) contacting the pH-adjusted aqueous eluate solution with an organic extractant solution comprising o-mercaptobenzoic acid, a quaternary alkylammonium salt, and an inert organic solvent to transfer a portion of the tungsten values to the organic extractant solution;
- (f) contacting the tungsten-containing organic extractant solution with an aqueous stripping solution to transfer a portion of the tungsten values to said aqueous stripping solution and to regenerate said organic extractant solution;
- (g) recycling the regenerated organic extractant solution to step e;
- and
- (h) recovering tungsten values from the aqueous stripping solution,
- whereby the tungsten recovered contains less than 1 mole percent contaminating boron.
A process for recovering tungsten substantially free of contaminating boron from aqueous media containing tungsten and boron comprising the steps of:
- (a) adjusting the pH of said aqueous medium to a value below about pH 8;
- (b) contacting the pH-adjusted aqueous medium with an ion exchange resin comprising a copolymer of 8-hydroxyquinoline, ethylenediamine, resorcinol, and formaldehyde to load said resin with tungsten and boron values from said aqueous medium;
- (c) eluting the loaded resin with an aqueous eluant solution to selectively recover a portion of the tungsten from said loaded resin;
- (d) adjusting the pH of the tungsten-containing aqueous eluate solution to a value below about pH 3;
- (e) contacting the pH-adjusted aqueous eluate solution with an organic extractant solution comprising o-mercaptobenzoic acid, a quaternary alkylammonium salt, and an inert organic solvent to transfer a portion of the tungsten values to the organic extractant solution;
- (f) contacting the tungsten-containing organic extractant solution with an aqueous stripping solution of a base to transfer a portion of the tungsten values to said aqueous stripping solution and to regenerate said organic extractant solution;
- (g) recycling the regenerated organic extractant solution to step e;
- and
- (h) recovering tungsten values from the aqueous stripping solution,
- whereby the tungsten recovered by said process contains less than 1 mole percent contaminating boron.
Dependencies are inferred from the claim text.