Hydrometallurgical solvent extraction methods

Patent metadata

Field	Value
Publication number	US-12378633-B2
Application number	US-201916458905-A
Country	US
Kind code	B2
Filing date	Jul 1, 2019
Priority date	Jul 5, 2018
Publication date	Aug 5, 2025
Grant date	Aug 5, 2025

Abstract

A hydrometallurgical solvent extraction method includes mixing an aqueous metal ion solution with an organic solution of metal extraction reagent to form a mixture, and allowing the aqueous metal ion solution and organic solution to phase separate from the mixture; wherein prior to mixing the aqueous metal ion solution and the organic solution, a water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups selected from the group consisting of sulfonated polystyrene; an addition polymer including at least one of styrene-4-sulfonic acid and 2-acrylamido-2-methylpropane sulfonic acid; naphthalene sulfonic acid-formaldehyde condensate; lignosulfonate; salts thereof; and mixtures thereof, is added to the aqueous metal ion solution, the organic solution, or to both the aqueous metal ion solution and the organic solution. The water-soluble or water-dispersible polymer can also be added simultaneously with or after mixing of the aqueous metal ion solution and the organic solution.

First claim

What is claimed is:

1. A hydrometallurgical solvent extraction method for preventing or mitigating crud within a solvent extraction circuit, the method comprising
mixing, within a mixing vessel or extraction column of a solvent extraction circuit, an aqueous metal ion solution with an organic solution of metal extraction reagent capable of binding with metal ions and transferring the metal ions from the aqueous solution to the organic solution to form a mixture, and
allowing the aqueous metal ion solution and organic solution to phase separate from the mixture;
wherein prior to mixing the aqueous metal ion solution and the organic solution, and prior to or during crud formation, a water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups selected from the group consisting of sulfonated polystyrene; an addition polymer comprising at least one of styrene-4-sulfonic acid and 2-acrylamido-2-methylpropane sulfonic acid; naphthalene sulfonic acid-formaldehyde condensate; lignosulfonate; salts thereof; and mixtures thereof, is added to the aqueous metal ion solution, the organic solution, or to both the aqueous metal ion solution and the organic solution to prevent or mitigate crud formation within the mixing vessel, the extraction column and/or a settler after the mixing vessel, of the solvent extraction circuit.

2. The method of claim 1 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups is added to the aqueous metal ion solution.

3. The method of claim 1 , wherein the aqueous metal ion solution is a pregnant leach solution, the organic solution is a partially loaded or barren organic solution, and the pregnant leach solution is extracted with the partially loaded or barren organic solution to generate a raffinate and a loaded organic solution.

4. The method of claim 1 , wherein the aqueous metal ion solution is a recycled raffinate solution which has been separated from the organic solution.

5. The method of claim 1 , wherein the aqueous metal ion solution is a lean aqueous electrolyte solution, and the loaded organic solution is stripped with the lean aqueous electrolyte solution to generate a rich aqueous electrolyte solution and a barren organic solution.

6. The method of claim 1 , wherein the metal extraction reagent is dissolved in an organic solvent to form the organic solution, wherein the organic solvent comprises aromatic paraffins, aliphatic paraffins, naphthas, or a combination comprising at least one of the foregoing organic solvents.

7. The method of claim 1 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises a sulfonated polystyrene with a degree of sulfonation of 1 to 100 mol %, based on the moles of styrene repeat units of polystyrene before sulfonation, salts thereof, or a combination comprising at least one of the foregoing water-soluble or water-dispersible polymers.

8. The method of claim 7 , wherein the water-soluble or water-dispersible polymer is a sulfonated polystyrene or salt thereof having 65 to 95 mol % sulfonation, based on the moles of styrene repeat units of polystyrene before sulfonation.

9. The method of claim 7 , wherein the sulfonated polystyrene or salt thereof has a number-average molecular weight of 300 to 100,000 g/mol and a polydispersity of 1 to 3, as measured by size exclusion chromatography against 100% sulfonated polystyrene standards.

10. The method of claim 9 , wherein the sulfonated polystyrene or salt thereof has a number-average molecular weight of 500 to 10,000 g/mol, as measured by size exclusion chromatography against 100% sulfonated polystyrene standards.

11. The method of claim 1 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups is selected from the group consisting of poly(styrene-4-sulfonic acid); poly(2-acrylamido-2-methylpropane sulfonic acid); copolymers of 2-acrylamido-2-methylpropane sulfonic acid and acrylamide; copolymers of styrene-4-sulfonic acid and acrylamide; copolymers of styrene and 2-acrylamido-2-methylpropane sulfonic acid, wherein the amount of 2-acrylamido-2-methylpropane sulfonic acid is greater than or equal to 20 mole %; salts thereof; and mixtures thereof.

12. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises poly(styrene-4-sulfonic acid), salts thereof, or mixtures thereof.

13. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises poly(2-acrylamido-2-methylpropane sulfonic acid), salts thereof, or mixtures thereof.

14. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises copolymers of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and acrylamide (AMD),
wherein the molar ratio of AMPS:AMD is from 30:70 to 90:10, salts thereof, or mixtures thereof.

15. The method of claim 14 , wherein the molar ratio of AMPS:AMD is from 50:50 to 90:10.

16. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises copolymers of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and styrene, wherein the molar ratio of AMPS is greater than 40%, salts thereof, or mixtures thereof.

17. The method of claim 16 , wherein the molar ratio of AMPS is greater than 60%.

18. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises copolymers of styrene-4-sulfonic acid (SS) and acrylamide (AMD), wherein the molar ratio of SS:AMD is from 30:70 to 90:10, salts thereof, or mixtures thereof.

19. The method of claim 18 , wherein the molar ratio of SS:AMD is from 60:40 to 80:20.

20. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises naphthalene sulfonic acid-formaldehyde condensate, salts thereof, or mixtures thereof.

21. The method of claim 11 , wherein the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate salt groups comprises lignosulfonate, salts thereof, or mixtures thereof.

22. The method of claim 1 , wherein the aqueous metal ion solution and organic solution are mixed in aqueous continuity.

23. The method of claim 1 , wherein the aqueous metal ion solution and organic solution are mixed in organic continuity.

24. The method of claim 1 , wherein the metal ion comprises copper, cadmium, chromium, cobalt, molybdenum, nickel, tin, uranium, vanadium, zinc, lithium, gold, a platinum group metal, an actinide, a rare earth element, or a combination comprising at least one of the foregoing metal ions.

25. The method of claim 1 , wherein an amount of water-soluble or water-dispersible polymer added to the aqueous metal ion solution, the organic solution, or to both the aqueous metal ion solution and the organic solution, is 0.01 to 1,000 milligrams per liter (mg/L) of aqueous metal ion solution.

26. The method of claim 1 , wherein an effective amount of the water-soluble or water-dispersible polymer comprising pendant sulfonic acid or sulfonate

Assignees

• Cytec Ind Inc

Inventors

• Moya Luis
• Soderstrom Matthew Dean
• Fischmann Adam James
• Moser Michael
• Zhang Lei

Classifications

• C22B3/26

  by liquid-liquid extraction using organic compounds · CPC title

• C22B3/41

  using a solution of normally solid organic compounds, e.g. dissolved polymers, sugars, or the like · CPC title

• Y02P10/20

  Recycling · CPC title

• C22B7/006 Primary

  Wet processes · CPC title

• C22B3/22 Primary

  by physical processes, e.g. by filtration, by magnetic means {, or by thermal decomposition} (treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title