Methods for purifying molybdenum-99

Patent metadata

Field	Value
Publication number	US-11189388-B2
Application number	US-201716325863-A
Country	US
Kind code	B2
Filing date	Aug 14, 2017
Priority date	Aug 16, 2016
Publication date	Nov 30, 2021
Grant date	Nov 30, 2021

Abstract

Methods for purifying the molybdenum-99 isotope are disclosed. Molybdenum-99 is loaded onto an anion exchange column and extracted. In some embodiments, the extraction solution may include nitric acid and nitrate salts. In other embodiments, a two stage elution is performed in which a nitric acid containing eluent and a hydroxide containing eluent are used in succession to extract molybdenum-99.

First claim

What is claimed is:

1. A method for purifying a molybdenum-99 feed stream comprising molybdenum-99, the method comprising:
contacting the molybdenum-99 feed stream with anion exchange media to adsorb molybdenum-99 onto the media; and
contacting the molybdenum-99 adsorbed media with an eluent solution comprising nitric acid and a nitrate salt.

2. The method as set forth in claim 1 wherein the molybdenum-99 feed stream comprises at least about 90 wt % molybdenum-99 on a dry basis.

3. The method as set forth in claim 1 wherein the nitrate salt is selected from the group consisting of alkali or alkaline earth-metal nitrate salts.

4. The method as set forth in claim 1 wherein the nitrate salt is selected from the group consisting of sodium nitrate and potassium nitrate.

5. The method as set forth in claim 1 wherein the molybdenum-99 feed stream comprises molybdenyl-99 ions.

6. The method as set forth in claim 1 wherein the molybdenum-99 feed stream is an aqueous hydroxide solution.

7. The method as set forth in claim 1 wherein the ratio of the mass of the eluent solution to the mass of molybdenum-99 in the molybdenum-99 feed stream is less than about 4:1.

8. A method for purifying a molybdenum-99 feed stream comprising molybdenum-99, the method comprising:
contacting the molybdenum-99 feed stream with anion exchange media to adsorb molybdenum-99 onto the media;
contacting the molybdenum-99 adsorbed media with a nitric acid-containing eluent solution; and
contacting the molybdenum-99 adsorbed media with a hydroxide-containing eluent solution containing hydroxide at a concentration of at least 0.1 M.

9. The method as set forth in claim 8 wherein the molybdenum-99 feed stream comprises at least about 90 wt % molybdenum-99 on a dry basis.

10. The method as set forth in claim 8 wherein the nitric acid-containing eluent comprises a nitrate salt selected from the group consisting of alkali or alkaline earth-metal nitrates.

11. The method as set forth in claim 8 wherein the nitric acid-containing eluent comprises a nitrate salt selected from the group consisting of sodium nitrate and potassium nitrate.

12. The method as set forth in claim 8 wherein the nitric acid-containing eluent solution is separate from the hydroxide-containing eluent solution, the nitic acid-containing eluent solution contacting the molybdenum-99 adsorbed media before the hydroxide-containing eluent solution.

13. The method as set forth in claim 8 wherein the nitric acid-containing eluent solution is separate from the hydroxide-containing eluent solution, the hydroxide-containing eluent solution contacting the molybdenum-99 adsorbed media before the nitic acid-containing eluent solution.

14. method as set forth in claim 8 wherein the molybdenum-99 feed stream comprises molybdenyl-99 ions.

15. The method as set forth in claim 8 wherein the molybdenum-99 feed stream is an aqueous hydroxide solution.

16. The method as set forth in claim 8 wherein the ratio of the mass of the nitric acid-containing eluent solution to the mass of molybdenum-99 in the molybdenum-99 feed stream is less than about 4:1.

17. The method as set forth in claim 8 wherein the ratio of the mass of the hydroxide-containing eluent solution to the mass of molybdenum-99 in the molybdenum-99 feed stream is less than about 4:1.

18. The method as set forth in claim 8 wherein the ratio of the mass of the sum of the nitric acid hydroxide-containing eluent solution and the hydroxide-containing eluent solution to the mass of molybdenum-99 in the molybdenum-99 feed stream is less than about 2:1.

Assignees

• Curium Us Llc

Inventors

• Barbosa Luis Antonio M M
• Dekker Frits
• Gerritsen Marjolijn
• Hermeler Mark David

Classifications

• C01G39/003

  Preparation involving a liquid-liquid extraction, an adsorption or an ion-exchange · CPC title

• G21G2001/0036

  Molybdenum · CPC title

• B01D15/426

  Specific type of solvent · CPC title

• G21G1/001 Primary

  Recovery of specific isotopes from irradiated targets · CPC title

• B01D15/363

  Anion-exchange · CPC title