PROCESS FOR EXTRACTING COBALT FROM A SOLUTION COMPRISING, IN ADDITION TO COBALT, ONE OR MORE OTHER METAL ELEMENTS

Abstract

A process for selectively extracting cobalt from a composition comprising cobalt and one or more other metal elements, wherein the process comprises the following steps: a) a step of forming a precipitate consisting of a coordination complex comprising cobalt, by bringing the solution into contact with at least one aromatic compound comprising at least two nitrogen atoms in its ring; b) a step of recovering the precipitate.

Claims

1.-18. (canceled)

19. A process for selective extraction of the cobalt from a solution comprising cobalt and one or more other metal elements, said process comprising the following steps: a) forming a precipitate consisting of a coordination complex comprising cobalt, said precipitate formed by placing said solution in contact with at least one aromatic compound comprising, in its ring, at least two nitrogen atoms; b) recovering the precipitate.

20. The process according to claim 19, wherein the coordination complex is a coordination polymer.

21. The process according to claim 19, wherein the other metal element(s) are transition metal elements.

22. The process according to claim 21, wherein the other metal element(s) are chosen from nickel, manganese, and the mixtures thereof.

23. The process according to claim 19, wherein the aromatic compound(s) are chosen from the monocyclic aromatic five-membered compounds comprising two carbon atoms, the bicyclic aromatic compounds, one of the rings of which is a five-membered ring including two nitrogen atoms, or the monocyclic aromatic six-membered compounds comprising two nitrogen atoms or three nitrogen atoms.

24. The process according to claim 23, wherein, when the aromatic compound(s) are monocyclic aromatic five-membered compounds satisfying at least one of the following formulas (I) to (IV): ##STR00005##

25. The process according to claim 23, wherein, when the aromatic compound(s) are bicyclic compounds satisfying the following formula (V): ##STR00006##

26. The process according to claim 23, wherein, when the aromatic compound(s) are monocyclic aromatic six-membered compounds comprising two nitrogen atoms satisfying at least one of the following formulas (VI) to (VIII): ##STR00007##

27. The process according to claim 23, wherein, when the aromatic compound(s) are monocyclic aromatic six-membered compounds comprising three nitrogen atoms satisfying at least one of the following formulas (IX) to (XI): ##STR00008##

28. The process according to claim 19, wherein the step of precipitation is carried out with stirring and without applying heat.

29. The process according to claim 19, wherein, when the solution, in addition to the cobalt, comprises, as other metal element(s), manganese, nickel, and mixtures thereof, the aromatic compound(s) are chosen from imidazole, 2-methylimidazole, and the mixtures thereof.

30. The process according to claim 19, further comprising, before step a), a previous step of preparing the solution comprising cobalt and one or more other metal elements.

31. The process according to claim 19, further comprising, after step b), a step of recovery, from the precipitate, of the aromatic compound(s) comprising at least two nitrogen atoms.

32. The process according to claim 31, wherein the step of recovery comprises the following operations: an operation of solubilizing the precipitate thus recovered; an operation of precipitating or crystallizing the aromatic compound(s) comprising at least two nitrogen atoms; an operation of recovering by filtration the aromatic compound(s) thus precipitated.

33. A process for manufacturing a simple oxide of cobalt comprising a step of implementing the process for selectively extracting cobalt as defined according to claim 19 and a step of heat treatment by calcination of the precipitate coming from the extraction process.

34. A process for manufacturing a mixed oxide of cobalt and of at least one other element comprising a step of implementing the process for selectively extracting cobalt as defined according to claim 19 and a step of heat treatment of the precipitate coming from the extraction process in the presence of a source of the other element(s).

35. A process for manufacturing a salt comprising a cobalt cation and an anion comprising a step of implementing the process for extracting cobalt as defined according to claim 19 and a step of dissolving the precipitate coming from the extraction process and a step of forming the salt by placing the solution coming from the dissolution in contact with the component anion of the salt.

36. A process for manufacturing a salt comprising a cobalt cation and an anion comprising a step of implementing the process for extracting cobalt as defined according to claim 19, a step of dissolving the precipitate coming from the extraction process, a step of recrystallizing and recovering by filtration the aromatic compound(s) comprising two nitrogen atoms and a step of forming the salt by placing the filtrate in contact with the component anion of the salt.

Description

DETAILED DISCLOSURE OF SPECIFIC EMBODIMENTS

Example 1

[0063] This example illustrates the implementation of the process of the invention at ambient temperature by using 2-methylimidazole as the aromatic compound.

[0064] To do this, a model solution is prepared by dissolving 4.369 g of cobalt nitrate, 4.322 g of nickel nitrate and 3.846 g of manganese nitrate in 600 mL of methanol, the final solution obtained being equimolar since it contains as many moles of cobalt, moles of nickel as moles of manganese.

[0065] The model solution is then introduced into a reactor stirred at 200 rpm at ambient temperature.

[0066] In parallel, in a beaker, 29.5806 g of 2-methylimidazole are dissolved in 400 mL of methanol.

[0067] The solution contained in the beaker is added into the reactor maintained with stirring. The mixture is then left for one night with stirring and at ambient temperature. The next day, the solution is filtered on a Büchner filter and a violet powder is obtained. This powder is then left to dry in an oven for one night at 60° C.

[0068] The powder is then analyzed by X-ray diffraction, from which it was able to be deduced that the material obtained satisfies the following formula: Co(C.sub.4H.sub.5N.sub.2).sub.2 and has a structure of the zeolitic imidazolate type.

[0069] The powder was also analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES), which allowed to demonstrate that the cobalt selectively reacted with the 2-méthylimidazole since the ratio of the molar percentages of elements in the powder shows that the molar percentage of cobalt is greater than 90% (more specifically 93% for cobalt, 2% for nickel and 6% for manganese). In other words, for 100 g of powder recovered, 22.77 g correspond to cobalt, 0.381 g to nickel and 1.26 g to manganese.

Example 2

[0070] This example illustrates the implementation of the process of the invention at 75° C. by using imidazole as the aromatic compound.

[0071] To do this, a model solution is prepared by dissolving 4.369 g of cobalt nitrate, 4.322 g of nickel nitrate and 3.846 g of manganese nitrate in 300 mL of methanol, the final solution obtained being equimolar since it contains as many moles of cobalt, moles of nickel as moles of manganese.

[0072] The model solution is introduced into the Teflon jacket of an autoclave having a 1-liter volume.

[0073] In parallel, in a beaker, 24.529 g of imidazole are dissolved in 200 mL of methanol.

[0074] The solution contained in the beaker is added into the Teflon jacket of the autoclave with the solution containing the cations. The autoclave is then closed and placed into an oven at 75° C. for two days. The solution is then filtered on a Büchner filter and a violet powder is obtained. This powder is then placed to dry in an oven at 60° C. for one night after having been rinsed with ethanol.

[0075] The powder was analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES), which allowed to demonstrate that the cobalt selectively reacted with the imidazole since the ratio of the molar percentages of elements in the powder shows that the molar percentage of cobalt is greater than 90% (more specifically 96% for cobalt, 2.2% for nickel and 1.8% for manganese). In other words, for 100 g of powder recovered, 22.71 g correspond to cobalt, 0.53 g corresponding to nickel and 0.41 g to manganese.