Hydrogen trapper compound, method for the production and uses thereof

1. A process for manufacturing a hydrogen-trapping compound, comprising at least one mineral compound of general formula:

MX(OH)

wherein:

M represents a divalent transition element;

O represents an oxygen atom;

X represents an atom of group 16 of the Periodic Table of the Elements, excluding O; and

H represents a hydrogen atom, comprising:

mixing, in aqueous solution, at least one dissolved salt of dissolved X 2− and at least one dissolved metal salt of M forming a precipitate of the at least one mineral compound of the formula MX(OH); wherein the precipitate is suspended in the aqueous phase.

2. The process of claim 1 , wherein the X 2− salt is Na 2 X , (NH 4 ) 2 X , Li 2 X , K 2 X or a mixture thereof.

3. The process of claim 1 , wherein the metal salt of M is selected from the group consisting of: MSO 4 .xH 2 O; M(NO 3 ) 2 ; M(ClO 4 ) 2 .xH 2 O; and MCl 2 ; wherein M represents a divalent transition element; and wherein x is a number greater than or equal to zero.

4. The process of claim 3 , wherein M is Co or Ni.

5. The process of claim 3 , wherein X is S.

6. The process of claim 1 , wherein the mixing in aqueous solution is carried out a pH of 4 to 12.

7. The process of claim 1 , wherein the molar ratio of the concentrations [X 2− ]/[M 2+ ]is from 0.875:1 to 1.5:1.

8. The process of claim 1 , wherein the at least one precipitated metal salt is extracted from the suspension in the aqueous phase; wherein extraction comprises: filtering, washing with water, and drying.

9. The process of claim 1 , wherein M is selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu and Zn.

10. The process of claim 1 , wherein X is selected from the group consisting of S, Se, Te and Po.

11. A method of encapsulating a solid waste comprising:

a) encapsulating the solid waste and a hydrogen-trapping compound, comprising at least one mineral compound of general formula:

MX(OH)

wherein:

M represents a divalent transition element;

O represents an oxygen atom:

X represents an atom of group 16 of the Periodic Table of the Elements, excluding O: and

H represents a hydrogen atom, with an organic encapsulation material to form an encapsulant; wherein prior to encapsulation the solid waste, the hydrogen-trapping compound, and the organic encapsulation material are heated; and wherein prior to encapsulation the organic encapsulation material is liquefied;

b) cooling the encapsulant; and

c) solidifying the encapsulant.

12. The method of claim 11 , wherein the organic encapsulation material is a bitumen.

13. The method of claim 12 , wherein the hydrogen-trapping compound is mixed with the bitumen in an amount of 1.5 to 82% in total, expressed as mass of trapping compound with respect to the mass of bitumen.

14. The method of claim 11 , wherein the solid waste is non-radioactive.

15. The method of claim 11 , wherein the solid waste is radioactive.

16. The method of claim 15 , wherein the radioactive waste represents at least 45 wt % of the total mass of the solid waste encapsulated with the composite organic material.

17. The method of claim 15 , further comprising chemically coprecipitating the radioactive waste in solid form and the hydrogen-trapping compound in order to obtain a solid phase comprising a mixture of the radioactive solid waste and of the hydrogen-trapping compound prior to being encapsulated.

18. The method of claim 11 , wherein M is selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu and Zn.

19. The method of claim 11 , wherein X is selected from the group consisting of S, Se, Te and Po.

20. The method of claim 11 , wherein M is Co or Ni.

21. The method of claim 11 , wherein X is S.

22. An organic material for encapsulating radioactive waste, comprising an organic encapsulation material and at least one hydrogen-trapping compound, comprising at least one mineral compound of general formula:

MX(OH)

wherein:

M represents a divalent transition element;

O represents an oxygen atom;

X represents an atom of group 16 of the Periodic Table of the Elements, excluding O; and

H represents a hydrogen atom.

23. The organic material for encapsulating radioactive waste of claim 22 , wherein the organic encapsulation material is a bitumen.

24. The organic material for encapsulating radioactive waste of claim 22 , wherein the at least one hydrogen-trapping compound represents in total an amount of 1.5 to 82% expressed as mass of trapping compound with respect to the mass of bitumen.

25. The organic material of claim 22 , wherein M is selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu and Zn.

26. The organic material of claim 22 , wherein X is selected from the group consisting of S, Se, Te and Po.

27. The organic material of claim 22 , wherein M is Co or Ni.

28. The organic material of claim 22 , wherein X is S.

29. A method for trapping hydrogen comprising contacting the hydrogen with at least one mineral compound of general formula:

MX(OH)

wherein:

M represents a divalent transition element;

O represents an oxygen atom;

X represents an atom of group 16 of the Periodic Table of the Elements, excluding O; and

H represents a hydrogen atom.

30. The method of claim 29 , wherein the hydrogen is produced by radiolysis of a radioactive waste and wherein the trapping is conducted within an organic material which encapsulates the both the hydrogen-trapping compound and the radioactive waste.

31. The method of claim 30 , wherein the organic material is bitumen.

32. The method of claim 29 , wherein M is selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu and Zn.

33. The method of claim 29 , wherein X is selected from the group consisting of S, Se, Te and Po.

34. The method of claim 29 , wherein M is Co or Ni.

35. The method of claim 29 , wherein X is S.