Adsorbent composition for argon purification

Patent metadata

Field	Value
Publication number	US-9457337-B2
Application number	US-201313782682-A
Country	US
Kind code	B2
Filing date	Mar 1, 2013
Priority date	Mar 1, 2013
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

An optimal material composition that allows for the purification of at least one feed component from a fluid feed stream such that the adsorbent has an oxygen capacity of at least 10 weight percent is described. More specifically, the material is an adsorbent for purification of a fluid feed stream having an oxygen to argon selectivity greater than or equal to a ratio of 3:1 and an oxygen capacity of greater than or equal to 10 weight percent, wherein the oxygen capacity is measured at a pressure in the range of about 9-10 Torr and a temperature of 77 degrees Kelvin after 4 hours of equilibration time and wherein the oxygen to argon selectivity is obtained by dividing the oxygen capacity by the argon capacity of the adsorbent measured at a pressure in the range of about 697-700 Torr and a temperature of 87 degrees Kelvin after 8 hours of equilibration time. The adsorption capacities are measured on a pure component basis.

First claim

We claim:

1. A material for purification of a fluid feed stream comprising a zeolite adsorbent having a silica to alumina ratio of less than or equal to 4:1, and partially ion exchanged with either a first low range or second high range of lithium charged balancing cations and/or a mixture of the two wherein said zeolite has pores defined by ring structures comprising at most 10 tetrahedrally coordinated atoms of the silicon and/or aluminum types having an oxygen to argon selectivity greater than or equal to a ratio of 3:1 and an oxygen capacity of greater than or equal to 10 weight percent, wherein said oxygen capacity is measured at a pressure in the range of about of about 9-10 Torr and a temperature of 77 degrees Kelvin after 4 hours of equilibration time and wherein said oxygen to argon selectivity is obtained by dividing said oxygen capacity by said argon capacity of said adsorbent measured at a pressure in a range of about 697-700 Torr and a temperature of 87 degrees Kelvin after 8 hours of equilibration time.

2. The material of claim 1 , wherein said oxygen to argon selectivity is greater than or equal to a ratio of 7:1.

3. The material of claim 1 , wherein said fluid feed stream is a liquid feed stream.

4. The material of claim 1 , wherein said adsorbent has an oxygen capacity of greater than or equal to 15 weight percent.

5. The material of claim 1 , wherein said adsorbent has an argon capacity of less than or equal to 3 weight percent.

6. The material of claim 1 , wherein said adsorbent is a lithium ion exchanged zeolite of type A wherein the non-lithium charge balancing counter cations are substantially sodium.

7. An adsorbent for purification of a fluid feed stream containing at least argon and oxygen by uptake of at least one feed component from said fluid feed stream, comprising: a zeolite adsorbent having a silica to alumina ratio of less than or equal to 4:1, and partially ion exchanged with either a first low range or a second high range of lithium charge balancing cations and/or a mixture of the two, wherein said first range contains between 15 and 55 percent and wherein said second range contains between 82 to 86 percent lithium charge balancing cations, wherein said zeolite has pores defined by ring structures comprising at most 10 tetrahedrally coordinated atoms of the silicon and/or aluminum types.

8. The adsorbent of claim 7 , wherein said zeolite has a pore size smaller than type 4A zeolite and larger than type 3A zeolite.

9. The adsorbent of claim 7 , wherein said zeolite has pores defined by rings comprising of at most 8 tetrahedrally coordinated atoms of the silicon and/or aluminum types.

10. The adsorbent of claim 7 , wherein said fluid feed stream is a liquid feed stream.

11. The adsorbent of claim 7 , wherein said zeolite is partially ion exchanged with 42 percent lithium charge balancing cations, and has an oxygen capacity of greater or equal to 20 weight percent, wherein the oxygen capacity is measured at in the range of about of about 9-10 Torr and a temperature of 77 degrees Kelvin after 4 hours of equilibration time.

12. An adsorbent for the purification process of a fluid feed stream comprising: a zeolite adsorbent having a silica to alumina ratio of less than or equal to 4:1, and partially ion exchanged with either a first low range or second high range of lithium charged balancing cations and/or a mixture of the two wherein said zeolite has pores defined by ring structures comprising at most 10 tetrahedrally coordinated atoms of the silicon and/or aluminum types having an oxygen to argon selectivity greater than or equal to a ratio of 3:1 and an oxygen capacity of greater than or equal to 10 weight percent, wherein said oxygen capacity is measured at a pressure in the range of about of about 9-10 Torr and a temperature of 77 degrees Kelvin after 4 hours of equilibration time, wherein said adsorbent is utilized in a fluid stream that is predominantly argon and less than or equal to 10,000 parts per million of oxygen, wherein the oxygen concentration after said purification process is completed, is less than or equal to 10 parts per million of oxygen in said fluid feed stream.

13. The adsorbent of claim 12 , wherein said oxygen to argon selectivity is obtained by dividing said oxygen capacity by the argon capacity of the adsorbent, measured at a pressure in the range of about of about 697 to 700 Torr and a temperature of 87 degrees Kelvin after 8 hours of equilibration time.

14. The adsorbent of claim 12 , wherein said first low range contains between 15 and 55 percent and wherein said second high range contains between 82 and 86 percent lithium charge balancing cations, and wherein the non-lithium charge balancing counter cations are substantially sodium.

15. The adsorbent of claim 14 , wherein said adsorbent has an oxygen capacity of greater than or equal to 15 weight percent.

16. The adsorbent of claim 14 , wherein said adsorbent has an argon capacity of less than or equal to 5 weight percent.

17. The adsorbent of claim 14 , wherein said argon capacity is less than or equal to 3 weight percent.

18. The adsorbent of claim 14 , wherein said oxygen to argon selectivity is greater than or equal to a ratio of 4:1.

19. The adsorbent of claim 14 , wherein said oxygen to argon selectivity is greater than or equal to a ratio of 7:1.

20. The adsorbent of claim 14 , wherein said zeolite is a type A zeolite.

21. The adsorbent of claim 14 , wherein the silica to alumina ratio is about 2:1.

22. The adsorbent of claim 14 , wherein said adsorbent is in the form of agglomerated particles having at most 20 weight percent of a binding agent.

23. The adsorbent of claim 22 , wherein said binding agent is selected from the group consisting of; a kaolin, sepiolite, halloysite, and attapulgite clay, purified versions thereof and/or mixtures thereof.

24. The adsorbent of claim 22 , wherein the mean particle size of said agglomerated adsorbent particles is less than or equal to 2.0 mm.

25. The adsorbent of claim 24 , wherein the mean particle size of said agglomerated adsorbent particles is in the range of 0.4 to 1.2 mm.

Assignees

• Barrett Philip A
• Pontonio Steven J
• Stephenson Neil A
• Kechagia Persefoni E
• Praxair Technology Inc

Inventors

• Barrett Philip A
• Pontonio Steven J
• Stephenson Neil A
• Kechagia Persefoni E

Classifications

• C01B23/0078

  Temperature swing adsorption · CPC title

• C01B2210/0034

  Argon · CPC title

• C01B23/0068

  Zeolites · CPC title

• C01B2210/0045

  Oxygen · CPC title

• B01J20/186 Primary

  Chemical treatments in view of modifying the properties of the sieve, e.g. increasing the stability or the activity, also decreasing the activity · CPC title