PROCESS FOR RADIOISOTOPE RECOVERY AND SYSTEM FOR IMPLEMENTING SAME

• US 20070065352A1
• Filed: 09/20/2006
• Published: 03/22/2007
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Battelle Energy Alliance LLC (Battelle Memorial Institute)
• Original Assignee: Battelle Energy Alliance LLC (Battelle Memorial Institute)
• Inventors: Horwitz, E., Meikrantz, David, Todd, Terry, Tranter, Troy
• Granted Patent: US 7,597,862 B2
• Time in Patent Office: Days
• US Class Current: 423/2
• CPC Class Codes: C22B 3/26 by liquid-liquid extraction using organic compounds
• CPC Class Codes: C22B 30/06 Obtaining bismuth
• CPC Class Codes: C22B 60/00 Obtaining metals of atomic number 87 or higher, i.e. radioactive metals
• CPC Class Codes: C22B 60/0295 obtaining other actinides except plutonium
• CPC Class Codes: G21G 4/00 Radioactive sources producing neutrons or other subatomic particles, X- or gamma rays, in fusion reactors G21B, in nuclear reactors G21C, by cosmic radiation G21H7/00, in accelerators H05H; X-ray tubes H01J35/00; gamma masers H01S4/00
• CPC Class Codes: Y02P 10/20 Recycling

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

1. A liquid-liquid extraction system for recovering at least one daughter isotope from a radioisotope mixture, comprising:

a first vessel configured to contact a first aqueous phase including at least one parent isotope with an organic phase, to extract the at least one parent isotope into the organic phase, and to separate the organic phase including the extracted at least one parent isotope from the first aqueous phase;

a second vessel operatively coupled to the first vessel and configured to substantially continuously contact the organic phase including the extracted at least one parent isotope with a second aqueous phase, to extract at least one daughter isotope from the organic phase into the second aqueous phase, and to separate the second aqueous phase including the extracted at least one daughter isotope from the organic phase; and

at least one separation column operatively coupled to the second vessel and configured to purify the at least one daughter isotope from the second aqueous phase.

2. The liquid-liquid extraction system of claim 1, wherein the first vessel is an annular centrifugal contactor.

3. The liquid-liquid extraction system of claim 1, wherein the second vessel is an annular centrifugal contactor.

4. The liquid-liquid extraction system of claim 1, wherein the at least one parent isotope comprises uranium and thorium.

5. The liquid-liquid extraction system of claim 1, wherein the at least one daughter isotope comprises at least one of actinium-225, radium-225, bismuth-213, and mixtures thereof.

6. The liquid-liquid extraction system of claim 1, wherein the at least one separation column is configured to purify at least one of actinium-225, radium-225, bismuth-213, and mixtures thereof from the second aqueous phase.

7. The liquid-liquid extraction system of claim 1, wherein the organic phase 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.

8. The liquid-liquid extraction system of claim 1, wherein the organic phase 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.

9. The liquid-liquid extraction system of claim 1, wherein the at least one separation column comprises an ion exchange column or an extraction column.

10. The liquid-liquid extraction system of claim 1, wherein the at least one separation column comprises a diglycolamide resin comprising a tetraalkyldiglycolamide extractant coated on inert support particles.

11. The liquid-liquid extraction system of claim 10, wherein the tetraalkyldiglycolamide extractant comprises 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.