Material and process for the filtration of nitric acid and NO2 from streams of air

• US 7,678,182 B2
• Filed: 06/15/2007
• Issued: 03/16/2010
• Est. Priority Date: 06/14/2004
• Status: Expired due to Fees

• Current Assignee: Guild Associates Incorporated
• Original Assignee: Guild Associates Incorporated
• Inventors: Rossin, Joseph A., Feaver, William B.
• Primary Examiner(s): LAWRENCE JR, FRANK M
• Application Number:
  US11/763,959
• Publication Number:
  US 20070245895A1
• Time in Patent Office: 1,005 Days
• Field of Search: 423/239.1, 423/239.2, 423/DIG.11, 423/DIG.22, 423/DIG.34, 502/60, 502/77, 502/85, 502/86, 502/62, 502/407, 502/414, 961/08, 961/53, 961/54, 951/29
• US Class Current: 96/153
• CPC Class Codes: B01D 2253/108 Zeolites
• CPC Class Codes: B01D 53/565 by treating the gases with solids
• CPC Class Codes: B01J 20/186 Chemical treatments in view of modifying the properties of the sieve, e.g. increasing the stability or the activity, also decreasing the activity
• CPC Class Codes: B01J 20/3021 Milling, crushing or grinding
• CPC Class Codes: B01J 20/3042 Use of binding agents; addition of materials ameliorating the mechanical properties of the produced sorbent
• CPC Class Codes: B01J 20/3078 Thermal treatment, e.g. calcining or pyrolizing
• CPC Class Codes: B01J 20/3204 Inorganic carriers, supports or substrates
• CPC Class Codes: B01J 20/3248 the functional group or the linking, spacer or anchoring group as a whole comprising at least one type of heteroatom selected from a nitrogen, oxygen or sulfur, these atoms not being part of the carrier as such
• CPC Class Codes: B01J 20/3251 comprising at least two different types of heteroatoms selected from nitrogen, oxygen or sulphur
• CPC Class Codes: B01J 2220/42 Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B01J 2220/56 Use in the form of a bed
• CPC Class Codes: B01J 2220/64 In a syringe, pipette, e.g. tip or in a tube, e.g. test-tube or u-shape tube
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

A material for filtering NO₂ and nitric acid vapors from air over a wide range of humidities and temperatures including a porous hydrophobic substrate and an amine is provided.

Claims

1. A material for filtering NO₂ and nitric acid vapors from air over wide range of humidities and temperatures, comprising:

a porous hydrophobic substrate comprising predominantly of an acidified form of a zeolite from the pentacil family; and

an amine.

2. The material of claim 1, wherein the porous hydrophobic substrate comprises predominantly ZSM-5.

3. The material of claim 1, wherein the porous hydrophobic substrate comprises predominantly ZSM-8.

4. The material of claim 1, wherein the porous hydrophobic substrate comprises predominantly ZSM-11.

5. The material of claim 1, wherein the material comprises from about 0.001% to about 20% by weight an amine selected from the group consisting of a primary amine, a secondary amine, an amine possessing both a primary and a secondary amine functional group, and mixtures thereof.

6. The material of claim 1, wherein the amine comprises at least one R—

NHCH₃ functional group.

7. The material of claim 1 wherein the amine comprises an amine salt.

8. A material for filtering NO₂ and nitric acid vapors from air over wide range of humidities and temperatures, comprising:

a porous hydrophobic substrate; and

an amine comprising at least one R—

NHCH₃ functional group.

9. The material of claim 8, wherein the porous hydrophobic substrate comprises a zeolite from the pentacil family.

10. The material of claim 8, wherein the porous hydrophobic substrate comprises predominantly ZSM-5.

11. The material of claim 8, wherein the porous hydrophobic substrate comprises predominantly ZSM-8.

12. The material of claim 8, wherein the porous hydrophobic substrate comprises predominantly ZSM-11.

13. The material of claim 8, wherein the porous hydrophobic substrate comprises predominantly of an acidified form of a zeolite from the pentacil family.

14. The material of claim 8, wherein the material comprises from about 0.001% to about 20% by weight an amine selected from the group consisting of a primary amine, a secondary amine, an amine possessing both a primary and a secondary amine functional group, and mixtures thereof.

15. The material of claim 8 wherein the amine comprises an amine salt.

16. A material for filtering NO₂ and nitric acid vapors from air over wide range of humidities and temperatures, comprising:

a porous hydrophobic substrate; and

an amine comprising an amine salt.

17. The material of claim 16, wherein the porous hydrophobic substrate comprises a zeolite from the pentacil family.

18. The material of claim 16, wherein the porous hydrophobic substrate comprises predominantly ZSM-5.

19. The material of claim 16, wherein the porous hydrophobic substrate comprises predominantly ZSM-8.

20. The material of claim 16, wherein the porous hydrophobic substrate comprises predominantly ZSM-11.

21. The material of claim 16, wherein the porous hydrophobic substrate comprises predominantly of an acidified form of a zeolite from the pentacil family.

22. The material of claim 16, wherein the material comprises from about 0.001% to about 20% by weight an amine selected from the group consisting of a primary amine, a secondary amine, an amine possessing both a primary and a secondary amine functional group, and mixtures thereof.