Adsorbent for and method of removing iodine compounds

• US 4,735,786 A
• Filed: 04/22/1985
• Issued: 04/05/1988
• Est. Priority Date: 04/25/1984
• Status: Expired due to Term

• Current Assignee: Toray Industries Incorporated
• Original Assignee: Toray Industries Incorporated
• Inventors: Shiomi, Hiromi, Inoue, Takehisa
• Primary Examiner(s): DEES, CARL
• Application Number:
  US06/726,019
• Time in Patent Office: 1,079 Days
• Field of Search: 502/60, 423/503, 423/241, 423/240 R
• US Class Current: 423/240.00R
• CPC Class Codes: B01J 20/18 Synthetic zeolitic molecular sieves
• CPC Class Codes: G21F 9/02 Treating gases

Abstract

Iodine and iodine compounds are removed by using an adsorbent comprising a silver loaded pentasil zeolite.

Claims

1. A method of removing iodine and iodine compounds from a gaseous stream, which comprises passing the gaseous stream containing iodine and iodine compounds through a layer of an adsorbent comprising a silver loaded pentasil zeolite having a silica/alumina ratio in the range of 15 to 100, whereby the iodine and iodine compounds are adsorbed in the zeolite.

2. A method according to claim 1, wherein the adsorbent contains silver in an amount of 5 to 15% by weight expressed as silver and based on the weight of the adsorbent.

3. A method according to claim 1, wherein the pentasil zeolite has a SiO₂ /Al₂ O₃ molar ratio of at least 15.

4. A methods according to claim 1, wherein the pentasil zeolite has a SiO₂ /Al₂ O₃ molar ratio of from 20 to 50.

5. A method according to claim 1, wherein the pentasil zeolite has a particle size of from 0.05 mm to 10 mm.

6. A methods according to claim 1, wherein the pentasil zeolite has a particle size of from 0.3 mm to 3 mm.

7. A method according to claim 1, wherein the pentasil zeolite has been prepared by calcination effected in air.

8. A methods according to claim 1, wherein the pentasil zeolite has been prepared by calcination effected in an inert gas.

9. A method according to claim 1, wherein the pentasil zeolite has been prepared by calcination effected in a hydrogen gas.

10. A method according to claim 1, wherein the silver loaded pentasil zeolite is prepared by an ion exchange method.

11. A method of removing iodine and iodine compounds from a gaseous stream under conditions of high humidity which comprises passing a gaseous stream containing iodine and iodine compounds through a layer of silver loaded pentasil zeolite whereby the iodine and iodine compounds are adsorbed in the zeolite wherein said zeolite contains 5 to 15% weight percent of silver based on the weight of the adsorbent and said zeolite has a SiO₂ /Al₂ O₃ molar ratio of from 15 to 100 and said zeolite has a particle size of 0.05 mm to 10 mm.