Oxidation Catalyst and Method for Destruction of CO, VOC and Halogenated VOC

• US 20110044874A1
• Filed: 08/21/2009
• Published: 02/24/2011
• Est. Priority Date: 08/21/2009
• Status: Active Grant

• Current Assignee: Clariant International AG (Clariant AG)
• Original Assignee: Sud-Chemie Incorporated (Clariant AG)
• Inventors: Dang, Zhongyuan, Cullen, Greg, Morrill, Martin, Singh, Nirmal
• Granted Patent: US 8,475,755 B2
• Time in Patent Office: Days
• US Class Current: 423/240.00S
• CPC Class Codes: B01D 2251/102 Oxygen
• CPC Class Codes: B01D 2255/1021 Platinum
• CPC Class Codes: B01D 2255/1026 Ruthenium
• CPC Class Codes: B01D 2255/2094 Tin
• CPC Class Codes: B01D 2255/407 Zr-Ce mixed oxides
• CPC Class Codes: B01D 2255/908 O2-storage component incorporated in the catalyst
• CPC Class Codes: B01D 2257/2062 Bromine compounds
• CPC Class Codes: B01D 2257/7027 Aromatic hydrocarbons
• CPC Class Codes: B01D 2257/704 Solvents not covered by groups B01D2257/702 - B01D2257/7027
• CPC Class Codes: B01D 2257/708 Volatile organic compounds V.O.C.'s
• CPC Class Codes: B01D 53/864 Removing carbon monoxide or hydrocarbons
• CPC Class Codes: B01D 53/8662 Organic halogen compounds
• CPC Class Codes: B01D 53/8668 Removing organic compounds not provided for in B01D53/8603 - B01D53/8665
• CPC Class Codes: B01J 23/63 with rare earths or actinides
• CPC Class Codes: B01J 29/0325 Noble metals
• CPC Class Codes: B01J 37/0242 Coating followed by impregnation

Abstract

An oxidation catalyst deposited on a substrate is described for the destruction of CO and volatile organic compounds, in particular halogenated organic compounds, from an emissions stream at temperatures from 250° C. to 450° C. The oxidation catalyst includes at least two platinum group metals, one of which is either platinum or ruthenium, supported on refractory oxides, such as a solid solution of CeO₂ and ZrO₂, and tin oxide and/or silica.

Claims

1. An oxidation catalyst for the destruction of CO and volatile organic compounds, in particular halogenated organic compounds, from an emissions stream, wherein the oxidation catalyst comprises

at least two platinum group metals, one of which comprises ruthenium or platinum,

a refractory oxides support comprising a solid solution of CeO₂ and ZrO₂;

and

one or both of silica and tin oxide.

2. The oxidation catalyst of claim 1 deposited on a substrate having a honeycomb or a monolithic structure wherein the substrate is produced from the group consisting of cordierite, mullite, iron-chromium alloy and stainless steel.

3. The oxidation catalyst of claim 1 wherein the two platinum group metals comprise ruthenium and platinum.

4. The oxidation catalyst of claim 1 wherein the platinum group metals consist essentially of ruthenium and platinum.

5. The oxidation catalyst of claim 3 wherein the ratio of ruthenium to platinum is 20 to 1 to 1 to 20.

6. The oxidation catalyst of claim 1 wherein the refractory oxides support is stabilized by blending with one or more rare earth metal oxides.

7. The oxidation catalyst of claim 6 wherein the rare earth metal oxides are selected from the group consisting of lanthanum oxide, cerium oxide, yttrium oxide, praseodymium oxide, neodymium oxide, and mixtures thereof.

8. The oxidation catalyst of claim 1 wherein the oxidation catalyst comprises tin oxide having a surface area from about 2 m²/g to 200 m²/g and a particle size of from about 1 to 20 micrometers.

9. The oxidation catalyst of claim 2 wherein the platinum group metals are deposited on the substrate at a loading that comprises from about 10 to about 200 g/cf (0.35 g/L to 7.1 g/L).

10. The oxidation catalyst of claim 1 wherein the oxidation catalyst comprises silica, which comprises from about 5% to about 50%, by weight, of the oxidation catalyst.

11. The oxidation catalyst of claim 1 wherein the oxidation catalyst comprises silica selected from the group consisting of amorphous silica, precipitated silica, molecular sieves, MCM-41, SBA-15, and combinations thereof.

12. The oxidation catalyst of claim 1 wherein the oxidation catalyst comprises silica comprising amorphous silica with a surface area more than about 200 m²/g, a pore size greater than about 100 angstrom and a particle size from about 0.5-20 micrometers.

13. The catalyst of claim 1 wherein the refractory metal oxides comprise from about 10% to about 95%, by weight of the oxidation catalyst.

14. The oxidation catalyst of claim 1 wherein the oxidation catalyst comprises tin oxide comprising about 5% to about 50%, by weight of the oxidation catalyst.

18. A method for treating a gas stream that contains CO and VOCs, including halogenated VOCs, and mixtures thereof, the method comprising

combining a gas stream that contains CO and VOCs, including halogenated VOCs, with oxygen;

and

contacting the combined oxygen-gas stream with the catalyst of claim 1 at a temperature from about 200°

C. to 500°

C.

19. The method of claim 18 wherein the gas stream comprises at least one halogenated organic compound.

20. The method of claim 18 wherein the gas stream comprises a brominated organic compound.

15. A process for the production of an oxidation catalyst deposited on a substrate for the destruction of CO and volatile organic compounds, in particular halogenated organic compounds, from an emissions stream comprising preparing an aqueous mixture slurry comprising a solid solution of CeO₂ and ZrO₂, and one or both of tin oxide and silica to form a mixture;

blending the mixture;

coating a substrate with the blended mixture;

drying and calcining the coated substrate;

depositing at least two platinum group metal precursor materials, comprising at least one of platinum and ruthenium, on the calcined coated substrate; and

drying and calcining the platinum group metals coated substrate.

16. The process of claim 15 wherein the aqueous mixture slurry is blended with a binder selected from the group consisting of colloidal alumina, colloidal silica, colloidal titania, colloidal zirconia, colloidal ceria and mixtures thereof.

17. A process for the production of an oxidation catalyst for the destruction of CO and volatile organic compounds, in particular halogenated organic compounds, from an emissions stream comprising

depositing at least two precious metal precursors on at least one component selected from the group consisting of a solid solution of CeO₂ and ZrO₂, and one or both of tin oxide and silica to form a mixture;

blending the mixture;

coating a substrate with the blended mixture;

drying and calcining the coated substrate.