Fiber filter and methods of use thereof

• US 5,942,323 A
• Filed: 01/27/1995
• Issued: 08/24/1999
• Est. Priority Date: 01/27/1995
• Status: Expired due to Term

• Current Assignee: Purafil, Inc. (FGI Equity LLC)
• Original Assignee: Purafil, Inc. (FGI Equity LLC)
• Inventors: England, William G.
• Primary Examiner(s): Krynski, William
• Assistant Examiner(s): Gray, J. M.
• Application Number:
  US08/378,807
• Time in Patent Office: 1,670 Days
• Field of Search: 428/372, 428/323, 428/328, 428/903, 428/281, 428/283, 428/289, 428/288, 210/500, 210/501, 210/503, 210/504, 210/505, 210/506, 210/507, 210/508, 210/348, 55/524, 55/527, 442/417
• US Class Current: 428/323
• CPC Class Codes: B01D 53/46 Removing components of defined structure
• CPC Class Codes: B01D 53/72 Organic compounds not provided for in groups B01D53/48 - B01D53/70, e.g. hydrocarbons
• CPC Class Codes: B01J 20/0222 Compounds of Mn, Re
• CPC Class Codes: B01J 20/04 comprising compounds of alkali metals, alkaline earth metals or magnesium
• CPC Class Codes: B01J 20/043 Carbonates or bicarbonates, e.g. limestone, dolomite, aragonite
• CPC Class Codes: B01J 20/08 comprising aluminium oxide or hydroxide; comprising bauxite
• CPC Class Codes: B01J 20/18 Synthetic zeolitic molecular sieves
• CPC Class Codes: B01J 20/28028 Particles immobilised within fibres or filaments
• CPC Class Codes: B01J 20/3212 consisting of a polymer obtained by reactions otherwise than involving only carbon to carbon unsaturated bonds
• CPC Class Codes: B01J 20/3236 containing metal, other than zeolites, e.g. oxides, hydroxides, sulphides or salts
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/2927 including structurally defined particulate matter
• CPC Class Codes: Y10T 442/699 Including particulate material other than strand or fiber material

Abstract

A fiber filter, method of preparing the fiber filter, and method of treating a fluid stream with the fiber filter are disclosed. The fiber filter comprises an inert fiber matrix, water, and a substrate bound to the fiber matrix that is capable of oxidizing or neutralizing a contaminant. More specifically, the substrate bound to the fiber matrix is sodium bicarbonate, impregnated activated alumina, impregnated zeolite, or a mixture thereof. The impregnate is a permanganate salt, sodium bicarbonate, or a mixture thereof. Improved efficiency of removal of undesirable compounds such as hydrogen sulfide and sulfur dioxide from fluid streams is achieved.

Claims

1. A fiber filter, consisting essentially of

(a) an inert fiber matrix;

(b) a substrate bound to the fiber matrix, wherein the substrate is impregnated with an impregnate; and

(c) water, wherein the water is in the impregnated substrate and wherein the amount of water in the impregnated substrate-bound fiber matrix is approximately 5 to 30% by weight;

wherein the substrate is selected from the group consisting of activated alumina and zeolite and the impregnate is selected from the group consisting of a permanganate salt, sodium bicarbonate and a mixture thereof, and wherein the bound impregnated substrate is capable of oxidizing or neutralizing a contaminant of a gaseous stream contacting the filter.

2. The filter of claim 1, wherein the fiber matrix is a woven or nonwoven synthetic fiber.

3. The filter of claim 2, wherein the synthetic fiber is selected from the group consisting of polyester, fiber glass, polypropylene, rayon, acetate, polyamides, nylon, and acrylics.

4. The filter of claim 2, wherein the matrix is steel wool.

5. The filter of claim 1, wherein the fiber matrix is nonwoven polyester fibers.

6. The filter of claim 1, wherein the permanganate salt is selected from the group consisting of potassium permanganate, sodium permanganate, magnesium permanganate, calcium permanganate, barium permanganate, and lithium permanganate.

7. The filter of claim 1, wherein the permanganate salt is potassium permanganate.

8. The filter of claim 1, wherein the amount of the fiber matrix in the impregnated substrate-bound fiber matrix is between approximately 5 to 75% by weight.

9. A fiber filter for oxidizing or neutralizing a contaminant in a gaseous stream, produced by a method comprising

coating a fiber matrix with an aqueous substrate solution or slurry, drying the substrate-coated fiber matrix until the concentration of water in the substrate-coated fiber matrix is between approximately 5 and 30% by weight and the concentration of the fiber matrix in the substrate-coated fiber matrix is between approximately 5 and 75% by weight,

wherein the substrate is selected from the group consisting of activated alumina and zeolite, the substrate is impregnated with one or more impregnates selected from the group consisting of a permanganate salt and sodium bicarbonate, and the fiber matrix is inert to the impregnate.

10. The filter of claim 9, wherein the fiber matrix is a woven or nonwoven synthetic fiber.

11. The filter of claim 10, wherein the synthetic fiber is selected from the group consisting of polyester, fiber glass, polypropylene, rayon, acetate, polyamides, nylon, and acrylics.

12. The filter of claim 9, wherein the fiber matrix is nonwoven polyester fibers.

13. The filter of claim 9, wherein the permanganate salt is selected from the group consisting of potassium permanganate, sodium permanganate, magnesium permanganate, calcium permanganate, barium permanganate, and lithium permanganate.

14. The filter of claim 9, wherein the permanganate salt is potassium permanganate.

15. The filter of claim 9, wherein the amount of substrate in the impregnated substrate-coated filter matrix after the drying step is approximately 5 to 75% by weight.

16. The filter of claim 9, wherein the fiber matrix is steel wool.

17. A fiber filter, consisting essentially of:

(a) a nonwoven polyester fiber matrix;

(b) a substrate bound to the fiber matrix, wherein the substrate is impregnated with potassium permanganate; and

(c) the impregnated substrate contains water;

wherein the substrate is selected from the group consisting of activated alumina and zeolite and the amount of nonwoven polyester fiber in the filter is approximately 5 to 75% by weight, the amount of substrate in the filter is approximately 5 to 75% by weight, the amount of potassium permanganate in the filter is approximately 1 to 20% by weight, and the amount of water in the filter is approximately 5 to 30% by weight.

18. A fiber filter, consisting essentially of:

(a) a nonwoven polyester fiber matrix;

(b) a substrate bound to the fiber matrix, wherein the substrate is impregnated with sodium bicarbonate and potassium permanganate; and

(c) the impregnated substrate contains water;

wherein the substrate is selected from the group consisting of activated alumina and zeolite and the amount of nonwoven polyester fiber in the filter is approximately 5 to 75% by weight, the amount of substrate in the filter is approximately 5 to 50% by weight, the amount of sodium bicarbonate in the filter is approximately 5 to 50% by weight, the amount of potassium permanganate in the filter is approximately 1 to 20% by weight, and the amount of water in the filter is approximately 5 to 30% by weight.