Method for the hydrometallurgical recovery of lithium, nickel and cobalt from the lithium transition metal oxide-containing fraction of used galvanic cells

1. A method for hydrometallurgical recovery of lithium, nickel, and cobalt from a fraction of used galvanic cells containing lithium transition metal oxides comprising the steps of:

introducing a fraction containing lithium transition metal oxides, wherein the transition metals are nickel, cobalt and/or manganese, having an aluminum content up to 5 wt. % and a particle size up to 500 μm into sulphuric acid having a concentration of 0.5 to 4 mol/l in an amount that is at least stoichiometric relative to the oxide content of the fraction containing lithium transition metal oxides and in a liquid/solid ratio in a range of 20 to 250 g/l;

solubilizing the lithium contained in the fraction containing lithium transition metal oxides with addition of at least a stoichiometric amount of hydrogen peroxide relative to the transition metal content of the fraction containing lithium transition metal oxide at temperatures of 35 to 70° C., wherein a solution containing lithium sulphate and sulphates of the transition metals is formed;

separating the lithium sulphate and the sulphates of the transition metals from a remaining residue; and

washing the remaining residue at least twice, wherein a washing solution containing lithium sulphate-containing washing solution is formed;

wherein the separated lithium sulphate and the lithium sulphate-containing washing solution are combined,

wherein the transition metals are precipitated as hydroxides in the pH range of 9 to 11, and the transition metals are separated and washed, and

wherein the combined lithium sulphate and the lithium sulphate-containing washing solution is converted by means of electrodialysis with bipolar membranes into lithium hydroxide.

2. A method according to claim 1 , wherein a fraction containing lithium transition metal oxide is used having an aluminum content up to 3 wt. %.

3. A method according to claim 1 , wherein a content of multivalent cations is reduced by means of an ion exchanger.

4. A method according to claim 1 , wherein the fraction containing the lithium transition metal oxide has a particle size up to 100 to 400 μm.

5. A method according to claim 1 , wherein the sulphuric acid is used at a concentration of 0.75 to 2.5 mol/l.

6. A method according to claim 1 , wherein the solid/liquid ratio is adjusted in the range of 30 to 230 g/l.

7. A method according to claim 1 , wherein the solubilizing step is carried out at temperatures of 35 to 65° C.

8. A method according to claim 1 , wherein the remaining residue is washed at least three times.

9. A method according to claim 1 , wherein the sulphuric acid and/or the hydrogen peroxide is used in excess.

10. A method according to claim 9 , wherein an excess of 0.1 to 10 mol % of the sulphuric acid and/or the hydrogen peroxide is used.

11. A method for hydrometallurgical recovery of lithium, nickel, and cobalt from a fraction of used galvanic cells containing lithium transition metal oxides, comprising the steps of:

introducing a fraction containing lithium transition metal oxides, wherein the lithium transition metal oxides are oxides comprising nickel, cobalt and/or aluminum, having a particle size up to 500 μm into sulphuric acid having a concentration of 0.5 to 4 mol/l in an amount that is at least stoichiometric relative to the oxide content of the fraction containing lithium transition metal oxide and in a liquid/solid ratio in the range of 20 to 300 g/l;

solubilizing the lithium contained in the fraction containing lithium transition metal oxides with addition of at least a stoichiometric amount of hydrogen peroxide relative to the transition metal content of the fraction containing lithium mixed oxide at temperatures of 35 to 70° C., wherein a solution containing lithium sulphate and sulphates of the transition metals is formed;

separating the lithium sulphates and sulphates of the transition metals from a remaining residue, and

washing the remaining residue at least twice, wherein a lithium sulphate-containing washing solution is formed, and

wherein the separated lithium sulphate and the lithium sulphate-containing washing solution are combined,

wherein the transition metals are precipitated as hydroxides in the pH range of 9 to 11, and the transition metals are separated and washed, and

wherein the combined lithium sulphate and the lithium sulphate-containing washing solution is converted into lithium hydroxide by means of electrodialysis with bipolar membranes.

12. A method according to claim 11 , wherein a content of multivalent cations is reduced by means of an ion exchanger.

13. A method according to claim 11 , wherein the fraction containing the lithium transition metal oxide has a particle size up to 100 to 400 μm.

14. A method according to claim 11 , wherein the sulphuric acid is used at a concentration of 0.75 to 2.5 mol/l.

15. A method according to claim 11 , wherein the solid/liquid ratio is in the range of 50 to 250 g/l.

16. A method according to claim 11 , wherein the solubilizing step is carried out at temperatures of 35 to 65° C.

17. A method according to claim 11 , wherein the remaining residue is washed at least three times.

18. A method according to claim 11 , wherein the sulphuric acid and/or the hydrogen peroxide is used in excess.

19. A method according to claim 18 , wherein an excess of 0.1 to 10 mol % of the sulphuric acid and/or the hydrogen peroxide is used.

20. A method for hydrometallurgical recovery of lithium, nickel, and cobalt from a lithium mixed-oxide-containing fraction of used galvanic cells, comprising the steps of introducing a fraction containing lithium transition metal oxides, wherein the lithium transition metal oxides are metal oxides of nickel, cobalt and/or aluminum, having a particle size up to 500 μm into hydrochloric acid having a concentration of 0.5 to 4 mol/l in an amount that is at least stoichiometric relative to the oxide content of the fraction containing lithium transition metal oxides, and in a solid/liquid ratio in the range of 10 to 150 g/l;

solubilizing the lithium contained in the fraction containing lithium transition metal oxides with addition of at least a stoichiometric amount of hydrogen peroxide with respect to the transition metal content of the fraction containing lithium metal oxides at temperatures of 35 to 70° C., wherein a solution containing lithium chloride and chlorides of the transition metals is formed;

separating the lithium chloride and chlorides of the transition metals from a remaining residue, and

washing the remaining residue at least twice to form a metal chloride-containing wash-solution, and

wherein the separated lithium chloride and chlorides of the transition metals and the metal chloride-containing wash-solution are combined,

wherein the transition metals are precipitated in the pH range of 9 to 11 as hydroxides, and the transition metals are separated and washed, and

wherein the combined lithium chloride and metal chloride-containing wash solution is converted by electrodialysis with bipolar membranes into lithium hydroxide.

21. A method according to claim 20 , wherein a content of multivalent cations is reduced by means of an ion exchanger.

22. A method according to claim 20 , wherein the fraction containing the lithium transition metal oxide has a particle size up to 100 to 400 μm.

23. A method according to claim 20 , wherein the hydrochloric acid is used at a concentration of 0.75 to 2.5 mol/l.

24. A method according to claim 20 , wherein the solid/liquid ratio is in the range of 15 to 120 g/l.

25. A method according to claim 20 , wherein the solubilizing step is carried out at temperatures of 35 to 65° C.

26. A method according to claim 20 , wherein the remaining residue is washed at least three times.

27. A method according to claim 20 , wherein the hydrochloric acid and/or the hydrogen peroxide is used in excess.

28. A method according to claim 27 , wherein an excess of 0.1 to 10 mol % of the hydrochloric acid and/or the hydrogen peroxide is used.