IP Library Granted Patent US 7,157,061
Granted Patent B2
US 7,157,061 · App. 10/949,675 · Granted Jan 2, 2007

Process for radioisotope recovery and system for implementing same

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Quick Facts
Patent No.
US 7,157,061
App. No.
10/949,675
Granted
Jan 2, 2007
Kind
B2
Abstract

A method of recovering daughter isotopes from a radioisotope mixture. The method comprises providing a radioisotope mixture solution comprising at least one parent isotope. The at least one parent isotope is extracted into an organic phase, which comprises an extractant and a solvent. The organic phase is substantially continuously contacted with an aqueous phase to extract at least one daughter isotope into the aqueous phase. The aqueous phase is separated from the organic phase, such as by using an annular centrifugal contactor. The at least one daughter isotope is purified from the aqueous phase, such as by ion exchange chromatography or extraction chromatography. The at least one daughter isotope may include actinium-225, radium-225, bismuth-213, or mixtures thereof. A liquid-liquid extraction system for recovering at least one daughter isotope from a source material is also disclosed.

Claims (56)

1. A method of recovering at least one daughter isotope from a radioisotope mixture, comprising:

providing a radioisotope mixture solution comprising at least one parent isotope;

extracting the at least one parent isotope into an organic phase;

substantially continuously contacting the organic phase with an aqueous phase;

substantially continuously extracting at least one daughter isotope into the aqueous phase; and

purifying the at least one daughter isotope from the aqueous phase.

2. The method of claim 1 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing an acidic solution comprising uranium and thorium.

3. The method of claim 1 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing the radioisotope mixture solution comprising uranium and thorium and having a nitric acid concentration ranging from approximately 2 M to approximately 6 M.

4. The method of claim 1 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing the radioisotope mixture solution comprising uranium and thorium and having a nitric acid concentration ranging from approximately 3 M to approximately 5 M.

5. The method of claim 1 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing a breeder reactor fuel that comprises uranium and thorium.

6. The method of claim 1 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing a breeder reactor fuel that comprises at least one of uranium-232, uranium-233, thorium-228, thorium-229, thorium-232, and mixtures thereof.

7. The method of claim 1 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase using an annular centrifugal contactor.

8. The method of claim 1 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises an extractant selected from the group consisting of n-tributyl phosphate, dibutyl phosphate, di-n-amyl-n-amylphosphonate, dibutyl butyl phosphonate, butyl dibutyl phosphinate, dibutyl cyclohexyl phosphonate, dibutyl chloromethyl phosphonate, tri(4-methylpentyl-2)phosphate, butyl phosphonate, di(4-methylpentyl-2)butyl phosphonate, di(4-methylpentyl-2)isobutyl phosphonate, di(4-methylpentyl-2)propyl phosphonate, and di(2-ethylbutyl)2-ethylbutyl phosphonate.

9. The method of claim 1 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises an extractant present from approximately 0.5 M to approximately 2.0 M.

10. The method of claim 1 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises a solvent selected from the group consisting of benzene, carbon tetrachloride, isopropyl ether, 1-octanol, 2-ethyl hexanol, 1-decanol, 1-octanoic acid, methyl isobutylketone, p-diisopropylbenzene, dodecane, n-heptane, a normal paraffinic hydrocarbon solvent, an isoparaffinic hydrocarbon solvent, and kerosene.

11. The method of claim 1 , wherein substantially continuously contacting the organic phase with the aqueous phase comprises substantially continuously contacting the organic phase with the aqueous phase that comprises from approximately 2 M to approximately 6 M nitric acid.

12. The method of claim 1 , wherein substantially continuously contacting the organic phase with the aqueous phase comprises substantially continuously contacting the organic phase with the aqueous phase that comprises from approximately 3 M to approximately 5 M nitric acid.

13. The method of claim 1 , wherein substantially continuously extracting the at least one daughter isotope into the aqueous phase comprises substantially continuously extracting the at least one daughter isotope into the aqueous phase using an annular centrifugal contactor.

14. The method of claim 1 , wherein purifying the at least one daughter isotope from the aqueous phase comprises purifying the at least one daughter isotope by ion exchange chromatography or extraction chromatography.

15. The method of claim 1 , wherein purifying the at least one daughter isotope from the aqueous phase comprises purifying at least one of actinium-225, radium-225, and mixtures thereof from the first aqueous phase.

16. The method of claim 1 , wherein purifying the at least one daughter isotope from the aqueous phase comprises removing the aqueous phase from a liquid-liquid extraction system and replacing the aqueous phase in the liquid-liquid extraction system with another aqueous phase.

17. The method of claim 1 , wherein purifying the at least one daughter isotope from the aqueous phase comprises removing tramp organics from the aqueous phase by extracting the tramp organics with an immiscible alcohol.

18. The method of claim 1 , wherein purifying the at least one daughter isotope from the aqueous phase comprises sorbing actinium-225 onto a diglycolamide resin, wherein the diglycolamide resin comprises a tetraalkyldiglycolamide extractant coated on inert support particles.

19. The method of claim 18 , wherein sorbing actinium-225 onto the diglycolamide resin comprises sorbing the actinium-225 onto the diglycolamide resin comprising N,N,N′,N′-tetra-N-alkyl-3-oxopentanediamide, N,N,N′,N′-tetra-n-octyl diglycolamide, N,N,N′,N′-tetra-(2-ethyl hexyl)-3-oxopentanediamide, or mixtures thereof as the tetraalkyldiglycolamide extractant.

20. The method of claim 1 , further comprising recovering the at least one daughter isotope from the aqueous phase.

21. The method of claim 1 , further comprising enabling the at least one daughter isotope to decay to at least one subsequent daughter isotope and recovering the at least one subsequent daughter isotope.

22. The method of claim 1 , further comprising enabling actinium-225 to decay to bismuth-213 and recovering the bismuth-213.

23. A method of recovering at least one daughter isotope from a radioisotope mixture, comprising:

providing a radioisotope mixture solution comprising at least one parent isotope;

contacting the radioisotope mixture solution with an organic phase;

extracting the at least one parent isotope into the organic phase;

separating the organic phase enriched in the at least one parent isotope from the radioisotope mixture solution depleted in the at least one parent isotope;

substantially continuously contacting the organic phase enriched in the at least one parent isotope with an aqueous phase;

substantially continuously extracting at least one daughter isotope into the aqueous phase;

separating the organic phase enriched in the at least one parent isotope from the aqueous phase enriched in the at least one daughter isotope; and

purifying the at least one daughter isotope from the aqueous phase.

24. The method of claim 23 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing the radioisotope mixture solution comprising uranium and thorium.

25. The method of claim 23 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing an acidic solution comprising uranium and thorium and having a nitric acid concentration ranging from approximately 2 M to approximately 6 M.

26. The method of claim 23 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing an acidic solution comprising uranium and thorium and having a nitric acid concentration ranging from approximately 3 M to approximately 5 M.

27. The method of claim 23 , wherein providing the radioisotope mixture solution comprising the at least one parent isotope comprises providing a breeder reactor fuel that comprises uranium and thorium.

28. The method of claim 23 , wherein providing the radioisotope mixture solution comprising at least one parent isotope comprises providing a breeder reactor fuel that comprises at least one of uranium-232, uranium-233, thorium-228, thorium-229, thorium-232, and mixtures thereof.

29. The method of claim 23 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase using an annular centrifugal contactor.

30. The method of claim 23 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises an extractant selected from the group consisting of n-tributyl phosphate, dibutyl phosphate, di-n-amyl-n-amylphosphonate, dibutyl butyl phosphonate, butyl dibutyl phosphinate, dibutyl cyclohexyl phosphonate, dibutyl chloromethyl phosphonate, tri(4-methylpentyl-2) phosphate, butyl phosphonate, di(4-methylpentyl-2)butyl phosphonate, di(4-methylpentyl-2)isobutyl phosphonate, di(4-methylpentyl-2)propyl phosphonate, and di(2-ethylbutyl)2-ethylbutyl phosphonate.

31. The method of claim 23 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises an extractant present from approximately 0.5 M to approximately 2.0 M.

32. The method of claim 23 , wherein extracting the at least one parent isotope into the organic phase comprises extracting the at least one parent isotope into the organic phase that comprises a solvent selected from the group consisting of benzene, carbon tetrachloride, isopropyl ether, 1-octanol, 2-ethyl hexanol, 1-decanol, 1-octanoic acid, methyl isobutylketone, p-diisopropylbenzene, dodecane, n-heptane, a normal paraffinic hydrocarbon solvent, an isoparaffinic hydrocarbon solvent, and kerosene.

33. The method of claim 23 , wherein substantially continuously contacting the organic phase enriched in the at least one parent isotope with the aqueous phase comprises substantially continuously contacting the organic phase with the aqueous phase that comprises from approximately 2 M to approximately 6 M nitric acid.

34. The method of claim 23 , wherein substantially continuously contacting the organic phase enriched in the at least one parent isotope with the aqueous phase comprises substantially continuously contacting the organic phase with the aqueous phase that comprises from approximately 3 M to approximately 5 M nitric acid.

35. The method of claim 23 , wherein substantially continuously extracting the at least one daughter isotope into the aqueous phase comprises substantially continuously extracting the at least one daughter isotope into the aqueous phase using an annular centrifugal contactor.

36. The method of claim 23 , wherein purifying the at least one daughter isotope from the aqueous phase comprises purifying the at least one daughter isotope by ion exchange chromatography or extraction chromatography.

37. The method of claim 23 , wherein purifying the at least one daughter isotope from the aqueous phase comprises purifying at least one of actinium-225, radium-225, and mixtures thereof from the first aqueous phase.

38. The method of claim 23 , wherein purifying the at least one daughter isotope from the aqueous phase comprises removing tramp organics from the aqueous phase by extracting the tramp organics with an immiscible alcohol.

39. The method of claim 23 , wherein purifying the at least one daughter isotope from the aqueous phase comprises sorbing actinium-225 onto a diglycolamide resin, wherein the diglycolamide resin comprises a tetraalkyldiglycolamide extractant coated on inert support particles.

40. The method of claim 39 , wherein sorbing actinium-225 onto the diglycolamide resin comprises sorbing the actinium-225 onto the diglycolamide resin comprising N,N,N′,N′-tetra-N-alkyl-3-oxopentanediamide, N,N,N′,N′-tetra-n-octyl diglycolamide, N,N,N′,N′-tetra-(2-ethyl hexyl)-3-oxopentanediamide, or mixtures thereof as the tetraalkyldiglycolamide extractant.

41. The method of claim 23 , wherein purifying the at least one daughter isotope from the aqueous phase comprises removing the first aqueous phase from a liquid-liquid extraction system and replacing the aqueous phase in the liquid-liquid extraction system with another aqueous phase.

42. The method of claim 23 , further comprising enabling the at least one daughter isotope to decay to at least one subsequent daughter isotope and recovering the at least one subsequent daughter isotope.

43. The method of claim 23 , further comprising enabling actinium-225 to decay to bismuth-213 and recovering the bismuth-213.

Assignments (4)
CORRECTIVE ASSIGNMENT TO CORRECT THE LANGUAGE CONCERNING RIGHTS ASSIGNED. PREVIOUSLY RECORDED ON REEL 015837 FRAME 0570. ASSIGNOR(S) HEREBY CONFIRMS THE WE DO ASSIGN UNTO BECHTEL BWXT IDAHO, LLC AND/OR ITS ASSIGNS, THE ENTIRE RIGHT, TITLE, AND INTEREST IN AND TO THE SAID INVENTION. Recorded Dec 21, 2006
From: MEIKRANTZ, DAVID H.; TRANTER, TROY J.; TODD, TERRY A.; HORWITZ, E. PHILIP
To: BATTELLE ENERGY ALLIANCE, LLC
Reel/Frame 018665/0708 →
CONFIRMATORY LICENSE Recorded Mar 24, 2005
From: BATTELLE ENERGY ALLIANCE, LLC
To: ENERGY, UNITED STATES DEPARTMENT OF
Reel/Frame 016388/0880 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 7, 2005
From: BECHTEL BWXT IDAHO, LLC
To: BATTELLE ENERGY ALLIANCE, LLC
Reel/Frame 016226/0765 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 24, 2004
From: MEIKRANTZ, DAVID H.; TODD, TERRY A.; TRANTER, TROY J.; HORWITZ, E. PHILIP
To: BECHTEL BWXT IDAHO, LLC
Reel/Frame 015837/0570 →