Claims
- 1. 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.
- 2. The process in accordance with claim 1 wherein said o-mercaptobenzoic acid is present in said organic extractant solution in a molar amount of from 2 to 20 times that of said tungsten in said aqueous eluate solution.
- 3. The process in accordance with claim 1 wherein said quaternary alkylammonium salt comprises a compound of the formula R.sub.1 R.sub.2 R.sub.3 (CH.sub.3)N.sup.+ X.sup.- where R.sub.1, R.sub.2, and R.sub.3 are selected from the group consisting of C.sub.8 to C.sub.10 straight chain hydrocarbon groups and X is bromide or chloride.
- 4. The process in accordance with claim 3 wherein said quaternary alkylammonium salt comprises methyl tricaprylylammonium chloride.
- 5. The process in accordance with claim 3 wherein said inert organic solvent is selected from the group consisting of .gtoreq.C.sub.7 hydrocarbons.
- 6. The process in accordance with claim 5 wherein said inert organic solvent further includes a C.sub.8 to C.sub.12 alcohol.
- 7. The process in accordance with claim 4 wherein said aqueous stripping solution comprises sodium hydroxide.
- 8. 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.
- 9. The process in accordance with claim 8 wherein said o-mercaptobenzoic acid is present in said organic extractant solution in a molar amount of from 2 to 20 times that of said tungsten in said aqueous eluate solution.
- 10. The process in accordance with claim 8 wherein said quaternary alkylammonium salt comprises a compound of the formula R.sub.1 R.sub.2 R.sub.3 (CH.sub.3)N.sup.+ X.sup.- where R.sub.1, R.sub.2, and R.sub.3 are selected from the group consisting of C.sub.8 to C.sub.10 straight chain hydrocarbon groups and X.sup.- is bromide or chloride.
- 11. The process in accordance with claim 10 wherein said quaternary alkylammonium salt is methyl tricaprylylammonium chloride.
- 12. The process in accordance with claim 10 wherein said inert organic solvent comprises at least 80 volume percent .gtoreq.C.sub.7 hydrocarbons with the balance comprising a C.sub.8 to C.sub.12 alcohol.
- 13. The process in accordance with claim 1 or claim 8 wherein said aqueous medium containing tungsten comprises Searles Lake brine.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of copending application Ser. No. 059,803 filed July 23, 1979, now abandoned which, in turn, is a continuation-in-part of application Ser. No. 018,488 filed Mar. 8, 1979, now abandoned.
US Referenced Citations (10)
Non-Patent Literature Citations (3)
Entry |
Morrison et al., "Solvent Extraction in Analytical Chemistry", John Wiley & Sons, N.Y., 1957, pp. 21-30. |
Altringer et al., "Bureau of Mines, RI 8315," Dept. of Interior, 1978, pp. 1-15. |
Flaschka et al., "Chelates in Anal. Chemistry," vol. 1, Marcel Dekker, Inc., N.Y., 1967, pp. 332-346. |
Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
59803 |
Jul 1979 |
|
Parent |
18488 |
Mar 1979 |
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