Catalytic converter comprising perovskite-type metal oxide catalyst

• US 6,531,425 B2
• Filed: 12/04/2001
• Issued: 03/11/2003
• Est. Priority Date: 04/10/1996
• Status: Expired due to Term

• Current Assignee: Catalyst Health Solutions Incorporated (UnitedHealth Group Incorporated)
• Original Assignee: Catalyst Health Solutions Incorporated (UnitedHealth Group Incorporated)
• Inventors: Golden, Stephen J.
• Primary Examiner(s): Silverman, Stanley S.
• Assistant Examiner(s): Nguyen, Cam N.
• Application Number:
  US10/006,968
• Publication Number:
  US 20020042341A1
• Time in Patent Office: 462 Days
• Field of Search: 502/302, 502/303, 502/304, 502/525
• US Class Current: 502/302
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/83 with rare earths or actinides
• CPC Class Codes: B01J 23/8892 Manganese
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/13 Potassium
• CPC Class Codes: B01J 2523/17 Copper
• CPC Class Codes: B01J 2523/23 Calcium
• CPC Class Codes: B01J 2523/24 Strontium
• CPC Class Codes: B01J 2523/25 Barium
• CPC Class Codes: B01J 2523/3706 Lanthanum
• CPC Class Codes: B01J 2523/67 Chromium
• CPC Class Codes: B01J 2523/72 Manganese
• CPC Class Codes: B01J 2523/821 Ruthenium
• CPC Class Codes: B01J 2523/822 Rhodium
• CPC Class Codes: B01J 2523/824 Palladium
• CPC Class Codes: B01J 2523/828 Platinum
• CPC Class Codes: B01J 2523/842 Iron
• CPC Class Codes: B01J 2523/845 Cobalt
• CPC Class Codes: B01J 2523/847 Nickel
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y10S 502/525 : Perovskite

Abstract

Perovskite-type catalyst consists essentially of a metal oxide composition is provided. The metal oxide composition is represented by the general formula A_a−xB_xMO_b, in which A is a mixture of elements originally in the form of single phase mixed lanthanides collected from bastnasite; B is a divalent or monovalent cation; M is at least one element selected from the group consisting of elements of an atomic number of from 23 to 30, 40 to 51, and 73 to 80; a is 1 or 2; b is 3 when a is 1 or b is 4 when a is 2; and x is a number defined by 0≦x<0.5. Methods of making and using the perovskite-type catalysts are also provided. The perovskite-type catalyst may be used to make a catalytic converter. Methods of making a catalytic converter are also provided.

Claims

1. A catalytic converter comprises:

(a) a perovskite-type catalyst comprising a metal oxide composition represented by the general formula;

2. The catalytic converter of claim 1, wherein the structure is a honeycomb support.

3. The catalytic converter of claim 2, wherein the honeycomb support is a ceramic honeycomb support.

4. The catalytic converter of claim 2, wherein the honeycomb support is a metal honeycomb support.

5. The catalytic converter of claim 1, wherein the structure is in the form of beads or pellets.

6. The catalytic converter of claim 1, wherein the perovskite-type catalyst has a formula selected from the group consisting of Ln_0.5Sr_0.5Mn_0.95Pt_0.05O₃, Ln_0.8Sr_0.2Mn_0.92Ni_0.05Pd_0.03O₃, Ln_0.8Sr_0.2Mn_0.94Pt_0.05Rh_0.01O₃, Ln_0.8Ba_0.2Mn_0.94Pd_0.06O₃, LnO_0.5Sr_0.5Mn_0.98Rh_0.02O₃, Ln_0.8Sr_0.2Co_0.9Ru_0.1O₃, Ln_0.8Sr_0.2Mn_0.9Ru_0.1O₃, Ln_0.8Sr_0.2Mn_0.9Ni_0.04Pd_0.06O₃, Ln_0.7Sr_0.3Mn_0.9Pd_0.1O₃, Ln_0.5Sr_0.5Mn_0.9Pd_0.1O₃, Ln_0.5Sr_0.5Mn_0.98Pd_0.02O₃, Ln_0.8Sr_0.2Mn_0.3, and a mixtures thereof.

7. The catalytic converter of claim 1, further comprising a carrier powder.

8. The catalytic converter of claim 7, wherein the carrier powder is an inert powder.

9. The catalytic converter of claim 8, wherein the inert powder is a gamma-alumina powder, a ceria-based powder, or a mixture thereof.

10. The catalytic converter of claim 7, wherein the carrier powder is selected from the group consisting of titania, silica, gamma alumina, alpha alumina, ceria, zirconia, ceria-zirconia, and a mixture thereof.

11. The catalytic converter of claim 7, wherein the carrier powder is a mixture of at least two different carrier powders.

12. The catalytic converter of claim 11, wherein the carrier powder is a ceria-alumina mixture.

13. The catalytic converter of claim 7, wherein the perovskite-type catalyst is in a bulk form.

14. The catalytic converter of claim 13, wherein the perovskite-type catalyst is mixed with the carrier powder to form a stable slurry suspension, and then the suspension is deposited on the support.

15. The catalytic converter of claim 7, wherein the perovskite-type catalyst is in the form of a dispersion.

16. The catalytic converter of claim 15, wherein the dispersed catalyst is prepared by a method comprising the steps of:

(a) forming a homogeneous solution of a single phase mixed lanthanide salt of element A and respective salts or oxides of elements B and M, wherein the ratio of A;

B;

M is the ratio represented by the general formula;

17. The catalytic converter of claim 16 comprising at least two different perovskite-type catalysts in the form of a dispersion, wherein the dispersed perovskite-type catalysts are slurry deposited onto the support individually, in combinations, or sequentially.

18. The catalytic converter of claim 17, wherein the two different perovskite-type catalysts are a perovskite-type catalyst with a formula Ln_0.5Sr_0.05Mn_0.95Pd_0.05O₃ and a perovskite-type catalyst with a formula Ln_0.8Sr_0.2Co_0.9Ru_0.1O₃.

19. The catalytic converter of claim 18 further comprising a second catalyst in the form of a dispersion, and the second catalyst is dispersed in the washcoat containing the bulk perovskite-type catalyst.

20. The catalytic converter of claim 19, wherein the second catalyst is a single base, a noble metal, or a mixture thereof.

21. The catalytic converter of claim 20, wherein the single base metal is selected from a group consisting of metallic elements with atomic numbers 3-4, 11-15, 19-32, 37-43, 48-52, 56-75, and 80-83.

22. The catalytic converter of claim 20, wherein the noble metal is selected from a group consisting of elements with atomic numbers 44, 45, 46, 47, 76, 77, 78 and 79.

23. The catalytic converter of claim 20, wherein the second catalyst is an oxide of Sr₂Pd_0.1.

24. The catalytic converter of claim 17, wherein the two different perovskite-type catalysts are a perovskite-type catalyst with a formula Ln_0.5Sr_0.5Mn_0.95Pd_0.05O₃ and a perovskite-type catalyst with a formula Ln_0.5Sr_0.5Mn_0.95Ru_0.05O₃.

25. The catalytic converter of claim 7 comprising a perovskite-type catalyst in a bulk form, wherein the carrier powder and bulk catalyst are slurry deposited as a washcoat on the support.

26. The catalytic converter of claim 25 further comprising a second perovskite-type catalyst in the form of a dispersion, wherein the second catalyst is dispersed on the washcoat of the support.

27. The catalytic converter of claim 26, wherein the first and second catalysts have the same or different formula.

28. The catalytic converter of claim 27, wherein the first catalyst is Ln_0.8Sr_0.2MnO₃, and the second catalyst is Ln_0.5Sr_0.5Mn_0.98Pd_0.02O₃.

29. The catalytic converter of claim 1, wherein the perovskite-type catalyst is in a bulk form.