Dry scrubbing air filtration media

• US 8,247,346 B2
• Filed: 03/18/2010
• Issued: 08/21/2012
• Est. Priority Date: 03/18/2009
• Status: Active Grant

• Current Assignee: Purafil, Inc. (FGI Equity LLC)
• Original Assignee: Purafil, Inc. (FGI Equity LLC)
• Inventors: England, William G.
• Primary Examiner(s): Hendrickson, Stuart
• Assistant Examiner(s): BERNS, DANIEL J
• Application Number:
  US12/726,746
• Publication Number:
  US 20100296990A1
• Time in Patent Office: 887 Days
• Field of Search: 502/400, 502/401, 502/404, 502/405, 502/407, 502/411, 502/413, 502/414, 502/415, 502/416, 502/417
• US Class Current: 502/401
• CPC Class Codes: B01D 2251/2067 Urea
• CPC Class Codes: B01D 2251/402 of magnesium
• CPC Class Codes: B01D 2251/404 of calcium
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/406 Ammonia
• CPC Class Codes: B01D 2257/70 Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
• CPC Class Codes: B01D 2259/40 Further details for adsorption processes and devices
• CPC Class Codes: B01D 53/02 by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/025 with wetted adsorbents; Chromatography analytical chromatography G01N30/00 - G01N30/96; for liquids B01D15/08
• CPC Class Codes: B01D 53/52 Hydrogen sulfide
• CPC Class Codes: B01D 53/58 Ammonia
• CPC Class Codes: B01D 53/72 Organic compounds not provided for in groups B01D53/48 - B01D53/70, e.g. hydrocarbons
• CPC Class Codes: B01D 53/80 Semi-solid phase processes, i.e. by using slurries
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/20 comprising free carbon; comprising carbon obtained by carbonising processes
• CPC Class Codes: B01J 20/22 comprising organic material
• CPC Class Codes: B01J 20/3007 Moulding, shaping or extruding
• CPC Class Codes: B01J 20/3204 Inorganic carriers, supports or substrates
• CPC Class Codes: B01J 20/3206 Organic carriers, supports or substrates
• CPC Class Codes: B01J 20/3236 containing metal, other than zeolites, e.g. oxides, hydroxides, sulphides or salts
• 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 2220/42 : Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: B01J 2220/46 : Materials comprising a mixture of inorganic and organic materials materials coated or impregnated on a carrier B01J20/32

Abstract

A solid air filtration medium includes an impregnate with an organic amine and an inorganic metal salt. The medium has from about 0.1 to about 25% by weight of impregnate. The impregnate contains from about 0.1 to about 5% by weight organic amine, and the organic amine includes aqueous urea, solid urea, melamine or mixtures thereof. The impregnate contains from about 0.1 to about 5% by weight metal salt, and the metal salt includes magnesium oxide, calcium oxide or mixtures thereof. The impregnate optionally further includes a surfactant such as polyacrylic acid. Methods for forming a solid air filtration medium having an impregnate containing an organic amine and an inorganic metal salt and methods for removing contaminants from a fluid stream are also provided.

Claims

1. A solid air filtration medium comprising an impregnate, wherein the impregnate comprises an organic amine and an inorganic metal salt, and wherein the inorganic metal salt comprises magnesium oxide, calcium oxide or combinations thereof.

2. The air filtration medium of claim 1, wherein the medium comprises from about 0.1 to about 25% by weight of impregnate.

3. The air filtration medium of claim 1, wherein the organic amine comprises aqueous urea, solid urea, melamine or mixtures thereof.

4. The air filtration medium of claim 1, wherein the impregnate comprises from about 0.1 to about 5% by weight organic amine.

5. The air filtration medium of claim 1, wherein the impregnate comprises from about 0.1 to about 5% by weight metal salt.

6. The air filtration medium of claim 1, wherein the impregnate further comprises a surfactant.

7. The air filtration medium of claim 6, wherein the impregnate comprises from about 0.1 to about 10% by weight surfactant.

8. The air filtration medium of claim 6, wherein the surfactant is polyacrylic acid.

9. A method for forming a solid air filtration medium comprising applying an impregnate to a porous substrate, wherein the impregnate comprises an organic amine and an inorganic metal salt and wherein the inorganic metal salt comprises magnesium oxide, calcium oxide or combinations thereof.

10. The method of claim 9, wherein the porous substrate is selected from the group consisting of activated alumina, silica gel, zeolite, kaolin, adsorbent clay, activated bauxite, activated carbon and combinations thereof.

11. The method of claim 10, wherein the porous substrate is activated alumina, activated carbon, or a combination thereof.

12. The method of claim 10, wherein the porous substrate is activated alumina, zeolite or a combination thereof.

13. The method of claim 9, wherein the impregnate is applied to the porous substrate in the form of a liquid solution.

14. The method of claim 13, wherein the impregnate is sprayed onto the porous substrate.

15. The method of claim 9, wherein the impregnate is applied to the porous substrate in the form of a powder.

16. The method of claim 9, wherein the impregnate is incorporated into the porous substrate prior to extrusion or pelletization of the substrate.

17. The method of claim 9, wherein the porous substrate is a woven or nonwoven material selected from the group consisting of glass fiber, crê

pe paper, Kraft paper, wool, steel wool, silk, cellulosic fiber fabrics, synthetic fiber fabrics and combinations thereof.