Method, catalyst, and photocatalyst for the destruction of phosgene

• US 6,596,664 B2
• Filed: 03/21/2002
• Issued: 07/22/2003
• Est. Priority Date: 04/20/2000
• Status: Expired due to Fees

• Current Assignee: KSE Limited
• Original Assignee: KSE Limited
• Inventors: Gerrish, David A., Kittrell, James R., Milazzo, Michael C.
• Primary Examiner(s): Langel, Wayne A.
• Assistant Examiner(s): Strickland, Jonas N
• Application Number:
  US10/104,308
• Publication Number:
  US 20020141923A1
• Time in Patent Office: 488 Days
• Field of Search: 502/305, 502/325, 502/326, 502/340, 502/344, 502/349, 502/182, 502/183, 502/242, 502/254, 502/309, 502/318, 502/319, 502/321, 502/329, 502/331, 502/338, 502/339, 423/240.R
• US Class Current: 502/182
• CPC Class Codes: B01D 2257/204 Inorganic halogen compounds
• CPC Class Codes: B01D 53/8659 Removing halogens or halogen compounds
• CPC Class Codes: B01D 53/8678 Removing components of undefined structure
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 21/066 Zirconium or hafnium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 21/18 Carbon
• CPC Class Codes: B01J 23/885 and copper
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 35/39 Photocatalytic properties

Abstract

In accordance with the present invention, a catalyst is described which comprises at least one metal selected from the group consisting of copper, zinc, iron, tungsten, molybdenum, and chromium distributed over a catalyst support comprising a material containing at least one of silicon, titanium, zirconium, magnesium, aluminum, and activated carbon. The catalyst is used to remove phosgene from a contaminated gas stream and/or reduce or eliminate phosgene from an effluent of a previously treated gas stream. At least one metal in the catalyst of the present invention is preferably present in an amount from about 0.001 wt % to about 15 wt %. When more than one metal is present, the combined metals preferably do not exceed 20 wt %. Catalysts in accordance with the present invention may be used as photocatalysts. Processes for using the catalysts and photocatalysts of the present invention are also described.

Claims

1. A catalyst comprising at least one metal selected from the group consisting of copper, zinc, iron, tungsten, molybdenum, chromium, and mixtures thereof distributed on a catalyst support wherein said catalyst support comprises a photocatalytically active support comprised of silicon in an amount from about 0.1 wt % to about 70 wt %, titanium dioxide in an amount from about 30 wt % to about 90 wt %, tungsten in an amount from 0.1 wt % to about 50 wt % and at least one member selected from the group consisting of platinum and palladium.

2. A catalyst according to claim 1, wherein said at least one metal is present in an amount from 0.001 wt % to about 15 wt %.

3. A catalyst according to claim 1, comprising at least two of said metals being distributed over said catalyst support with the total of said metals not exceeding 20 wt %.

4. A catalyst according to claim 1, wherein said at least one metal comprises tungsten or molybdenum in an amount from 0.015 wt % to about 5.0 wt %.

5. A catalyst according to claim 1, wherein copper and molybdenum are distributed on said catalyst support.

6. A catalyst according to claim 1, at least one member selected from the group consisting of platinum and palladium is present in an amount of less than or equal to about 10 wt %.

7. A catalyst according to claim 6, wherein said at least one member selected from the group consisting of platinum and palladium is present in an amount from about 0.1 wt % to 5.0 wt %.

8. A catalyst according to claim 1, wherein said tungsten is present in an amount from about 1.0 wt % to about 30 wt %.

9. A catalyst according to claim 1, wherein said support comprises less than or equal to 5 wt % of at least one member selected from the group consisting of platinum and palladium.

10. A catalyst for removing contaminants from a gas stream comprising a catalyst support formed from a material containing at least one member selected from the group consisting of silicon, titanium, zirconium, magnesium, aluminum, and activated carbon, and further comprising a material which forms a silicon-tungsten bond deposited on said catalyst support.

11. A catalyst according to claim 10, wherein said silicon-tungsten bond forming material comprises a silicon-tungsten compound.

12. A catalyst according to claim 10, wherein said silicon-tungsten bond forming material comprises a silicon containing material and a tungsten containing material.