Systems and methods for production of Xenon-133

Patent metadata

Field	Value
Publication number	US-11679979-B2
Application number	US-201916405703-A
Country	US
Kind code	B2
Filing date	May 7, 2019
Priority date	May 8, 2018
Publication date	Jun 20, 2023
Grant date	Jun 20, 2023

Abstract

Methods and systems for producing Xenon-133 are disclosed. A method for producing Xenon-133 includes collecting an off gas from a Molybdenum-99 production process in a storage tank. The off gas includes Xenon-133 and Krypton-85. The method further includes selectively adsorbing Xenon-133 from the off gas onto a charcoal column assembly such that Xenon-133 is selectively adsorbed onto the charcoal column assembly relative to Krypton-85. The method further includes desorbing the Xenon-133 from the charcoal column assembly by heating the charcoal column assembly, and condensing the Xenon-133 within a coil assembly.

First claim

What is claimed is:

1. A method for producing Xenon-133 comprising:
collecting an off gas from a Molybdenum-99 production process in a storage tank, the off gas including Xenon-133 and Krypton-85;
selectively adsorbing Xenon-133 from the off gas onto a charcoal column assembly such that Xenon-133 is selectively adsorbed onto the charcoal column assembly relative to Krypton-85;
desorbing the Xenon-133 from the charcoal column assembly by heating the charcoal column assembly; and
condensing the Xenon-133 within a coil assembly.

2. The method of claim 1 further comprising evacuating the coil assembly while the Xenon-133 is condensed within the coil assembly.

3. The method of claim 2 further comprising:
sealing the coil assembly after the coil assembly is evacuated; and
allowing the coil assembly to reach ambient temperature such that condensed Xenon-133 within the coil assembly evaporates into gaseous Xenon-133 within the coil assembly.

4. The method of claim 1 further comprising removing water vapor from the off gas prior to selectively adsorbing the Xenon-133 onto the charcoal column assembly, wherein removing water vapor from the off gas includes passing the off gas through a zeolite column assembly.

5. The method of claim 1 further comprising removing carbon dioxide from the off gas prior to selectively adsorbing the Xenon-133 onto the charcoal column assembly, wherein removing carbon dioxide from the off gas includes passing the off gas through a column assembly containing sodium-hydroxide coated silicon dioxide.

6. The method of claim 1 , wherein collecting an off gas from a Molybdenum-99 production process includes collecting the off gas from low-enriched uranium targets.

7. The method of claim 1 , wherein selectively adsorbing Xenon-133 from the off gas onto a charcoal column assembly includes:
cooling the charcoal column assembly to a temperature in the range of −5° C. to 10° C.; and
directing the off gas through the cooled charcoal column assembly.

8. The method of claim 1 , wherein desorbing the Xenon-133 from the charcoal column assembly includes heating the charcoal column assembly to a temperature of at least 70° C.

9. The method of claim 1 , wherein condensing the Xenon-133 within a cooled coil assembly includes:
cooling the coil assembly to a temperature less than −150° C.; and
passing the off gas through the cooled coil assembly while the coil assembly is at a temperature of less than −150° C.

10. A method for producing Xenon-133 comprising:
collecting an off gas from a Molybdenum-99 production process in a storage tank, the off gas including Xenon-133 and Krypton-85;
directing the off gas through a cooled charcoal column assembly such that Xenon-133 is selectively adsorbed onto the charcoal column assembly relative to Krypton-85;
heating the charcoal column assembly to a sufficient temperature to desorb the Xenon-133 from the charcoal column assembly;
flowing a carrier gas through the heated charcoal column assembly such that the Xenon-133 is desorbed from the charcoal column assembly; and
directing the carrier gas and the desorbed Xenon-133 through a cooled coil assembly such that the Xenon-133 condenses within the coil assembly.

11. The method of claim 10 further comprising evacuating the cooled coil assembly while the Xenon-133 is condensed within the coil assembly by:
fluidly connecting an outlet of the coil assembly to a vacuum source; and
fluidly connecting a flow restrictor between the outlet of the coil assembly and the vacuum source.

12. The method of claim 11 , wherein the flow restrictor includes one of a restrictor orifice and a needle valve.

13. The method of claim 10 further comprising fluidly connecting an outlet of the coil assembly to a vacuum source to evacuate the cooled coil assembly while the Xenon-133 is condensed within the coil assembly.

14. The method of claim 10 , wherein directing the off gas through a cooled charcoal column assembly includes directing the off gas through the cooled charcoal column assembly at a flow rate in the range of 1.2 normal liters per minute (NL/min) to 1.8 NL/min while the charcoal column assembly is at a temperature in the range of −5° C. to 10° C.

15. The method of claim 10 , wherein directing the off gas through a cooled charcoal column assembly includes directing the off gas through the cooled charcoal column assembly at a flow velocity in the range of 5 centimeters per second (cm/s) to 10 cm/s while the charcoal column assembly is at a temperature in the range of −5° C. to 10° C.

16. The method of claim 10 , wherein directing the carrier gas and the desorbed Xenon-133 through a cooled coil assembly includes directing the carrier gas and the desorbed Xenon-133 through the cooled coil assembly at a flow rate in the range of 140 normal-milliliters/minute (NmL/min) to 180 NmL/min while the coil assembly is at a temperature of less than −150° C.

17. The method of claim 13 , wherein fluidly connecting the outlet of the coil assembly to the vacuum source includes fluidly connecting the outlet of the coil assembly to an evacuated container having a pressure in the range of 200 milliBar (mBar) to 350 mBar.

18. The method of claim 13 , wherein fluidly connecting the outlet of the coil assembly to the vacuum source includes evacuating the coil assembly to a pressure less than 500 milliBar.

Assignees

• Curium Us Llc

Inventors

• Barbosa Luis Antonio M M
• Gerritsen Sven V
• Schackmann Martinus J A
• Gronland Paul A
• Hierholzer Brian

Classifications

• C01B23/0063 Primary

  Carbon based materials · CPC title

• Y02C20/40

  of CO2 · CPC title

• F25J3/0685

  separation of noble gases (from air F25J3/04642; in general C01B23/00) · CPC title

• G21G2001/0094

  Other isotopes not provided for in the groups listed above · CPC title

• F25J2270/904

  by liquid or gaseous cryogen in an open loop · CPC title