Perovskite-type metal oxide compounds and methods of making and using thereof

• US 20020042341A1
• Filed: 12/04/2001
• Published: 04/11/2002
• Est. Priority Date: 04/10/1996
• Status: Active Grant

• Current Assignee: Catalyst Health Solutions Incorporated (UnitedHealth Group Incorporated)
• Original Assignee: Catalyst Health Solutions Incorporated (UnitedHealth Group Incorporated)
• Inventors: Golden, Stephen J.
• Granted Patent: US 6,531,425 B2
• Time in Patent Office: Days
• US Class Current: 502/303
• 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 perovskite-type catalyst consisting essentially of a metal oxide composition represented by the general formula:

A_1-xB_xMO₃

wherein

A is a mixture of elements originally in the form of a single phase mixed lanthanide 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 22 to 30, 40 to 51, and 73 to 80; and

x is a number defined by 0≦

x<

0.5.

2. A perovskite-type catalyst of claim 1 having a formula Ln_{0 5}Sr_0.5Mn_{0 95}Pt_{0 05}O₃

3. A perovskite-type catalyst of claim 1 having a formula Ln_0.8Sr_0.2Mn_0.92Ni_0.05Pd_0.03O₃.

4. A perovskite-type catalyst of claim 1 having a formula Ln_0.8Sr_0.2Mn_{0 94}Pt_0.05Rh_{0 01}O₃.

5. A perovskite-type catalyst of claim 1 having a formula Ln_0.8Ba_0.2Mn_0.94Pd_0.06O₃

6. A perovskite-type catalyst of claim 1 having a formula Ln_{0 5}Sr_0.5Mn_0.98Rh_0.02O₃.

7. A perovskite-type catalyst of claim 1 having a formula Ln_{0 8}Sr_{0 2}Co_{0 9}Ru_0.1O₃.

8. A perovskite-type catalyst of claim 1 having a formula Ln_{0 8}Sr_{0 2}Mn_{0 9}Ru_0.1O₃.

9. A perovskite-type catalyst of claim 1 having a formula Ln_{0 8}Sr_{0 2}Mn_0.9Ni_{0 04}Pd_{0 06}O₃

10. A perovskite-type catalyst of claim 1 having a formula Ln_{0 7}Sr_{0 3}Mn_0.9Pd_0.1O₃

11. A perovskite-type catalyst of claim 1 having a formula Ln_{0 5}Sr_{0 5}Mn_{0 9}Pd_{0 1}O₃.

12. A perovskite-type catalyst of claim 1 having a formula Ln_{0 5}Sr_{0 5}Mn_{0 98}Pd_0.02O₃

13. A perovskite-type catalyst of claim 1 having a formula Ln_{0 8}Sr_{0 2} MnO₃.

15. The catalytic converter of claim 14, wherein the structure is a honeycomb support.

16. The catalytic converter of claim 15, wherein the honeycomb support is a ceramic honeycomb support.

17. The catalytic converter of claim 15, wherein the honeycomb support is a metal honeycomb support.

18. The catalytic converter of claim 14, wherein the structure is in the form of beads or pellets.

19. The catalytic converter of claim 14, wherein the perovskite-type catalyst has a formula selected from a 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, Ln_0.5Sr_0.5Mn_0.98Rh_0.02O₃, Ln_{0 8}Sr_0.2Co_0.9Ru_0.1O₃, Ln_0.8Sr_0.2Mn_0.9Ru_0.1O₃. Ln_0.8Sr_0.2Mn_{0 9}Ni_{0 04}Pd_0.06O₃. Ln_0.7Sr_{0 3}Mn_0.9Pd_{0 1}O₃. Ln_0.5Sr_{0 5}Mn_{0 9}Pd_0.1O₃. Ln_0.5Sr_0.5Mn_{0 98}Pd_{0 02} O₃. Ln_0.8Sr_{0 2}MnO₃, and a mixture thereof.

20. The catalytic converter of claim 14 further comprises a carrier powder.

21. The catalytic converter of claim 20, wherein the carrier powder is an inert powder.

22. The catalytic converter of claim 21, wherein the inert powder is a gamma-alumina powder, a ceria-based powder, or a mixture thereof.

23. The catalytic converter of claim 20, wherein the carrier powder is selected from a group consisting of titania, silica, gamma alumina, alpha alumina, ceria, zirconia, ceria-zirconia, and a mixture thereof.

24. The catalytic converter of claim 20, wherein the carrier powder is a mixture of at least two different carrier powders.

25. The catalytic converter of claim 24, wherein the carrier powder is a ceria-alumina mixture.

26. The catalytic converter of claim 14, wherein the perovskite-type catalyst is in a bulk form.

27. The catalytic converter of claim 20, wherein the perovskite-type catalyst is in a bulk form.

28. The catalytic converter of claim 27, 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.

29. The catalytic converter of claim 20, wherein the perovskite-type catalyst is in the form of a dispersion.

34. The catalytic converter of claim 20 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.

14. A catalytic converter comprises:

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

A_1-xB_xMO₃

wherein

A is a mixture of elements originally in the form of a single phase mixed lanthanide 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 22 to 30, 40 to 51, and 73 to 80;

x is a number defined by 0≦

x<

0.5; and

(b) a structure for supporting the catalyst.

30. The catalytic converter of claim 29, wherein the method of forming the dispersed catalyst comprises 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 same as their ratio in the formula A_1-xB_xM as defined in claim 14;

(b) impregnating the solution to the carrier powder; and

(c) calcining the carrier powder impregnated with the solution of step (a) to form the perovskite-type catalyst in the form of a dispersion.

31. The catalytic converter of claim 30 comprising at least two different perovskite-type catalysts in a dispersion form, wherein the dispersed perovskite-type catalysts are slurry deposited onto the support individually, in combinations, or sequentially.

32. The catalytic converter of claim 31, wherein the two different perovskite-type catalysts are a perovskite-type catalyst with a formula Ln_{0 5}Sr_{0 5}Mn_{0 95}Pd_{0 05}O₃ and a perovskite-type catalyst with a formula Ln_{0 8}Sr_{0 2}Co_{0 9}Ru_0.1O₃.

33. The catalytic converter of claim 31, wherein the two different perovskite-type catalysts are a perovskite-type catalyst with a formula Ln_{0 5}Sr_0.5Mn_{0 95}Pd_{0 05}O₃ and a perovskite-type catalyst with a formula Ln_{0 5}Sr_{0 5}Mn_{0 95}Ru_0.05O₃.

35. The catalytic converter of claim 34 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.

36. The catalytic converter of claim 35, wherein the first and second catalysts have the same or different formula.

37. The catalytic converter of claim 36, wherein the first catalyst is Ln_0.8Sr_0.2MnO₃, and the second catalyst is Ln_0.5Sr_0.5Mn_0.98Pd_0.02O₃.

38. The catalytic converter of claim 32 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.

39. The catalytic converter of claim 38, wherein the second catalyst is a single base, a noble metal, or a mixture thereof.

40. The catalytic converter of claim 39, 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, 80-83.

41. The catalytic converter of claim 39, wherein the noble metal is selected from a group consisting of elements with atomic numbers 44, 45, 46, 47, 76, 77, 78 and 79.

42. The catalytic converter of claim 39, wherein the second catalyst is the oxide of Sr₂Pd_0.1.

43. A method of making a catalytic converter comprising the steps of:

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

A_1-xB_xMO₃

wherein

A is a mixture of elements originally in the form of a single phase mixed lanthanide 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 22 to 30, 40 to 51, and 73 to 80;

x is a number defined by 0≦

x<

0.5; and

(b) providing a support structure having a surface;

(c) forming a stable slurry suspension of the perovskite-type catalyst; and

(d) depositing the suspension of the perovskite-type catalyst on the surface of the support structure.

44. The method of making a catalytic converter of claim 43, wherein the perovskite-type catalyst is in a bulk form.

45. The method of making a catalytic converter of claim 44 which further comprises the steps of providing a carrier powder and mixing the carrier powder into the stable slurry suspension of step (b).

46. The method of making a catalytic converter of claim 45, wherein the carrier powder is an inert powder.

47. The method of making a catalytic converter of claim 46, wherein the inert powder is a gamma-alumina powder, a ceria-based powder, or a mixture thereof.

48. The method of making a catalytic converter of claim 45, wherein the carrier powder is selected from a group consisting of titania, silica, gamma alumina, alpha alumina. ceria, zirconia, ceria-zirconia, and a mixture thereof.

49. The method of making a catalytic converter of claim 43, wherein the perovskite-type catalyst is in a form of dispersion.

50. The method of making a catalytic converter of claim 49, wherein the dispersion form of the perovskite-type catalyst is formed by the steps of:

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

B;

M is the same as their ratio in the formula A_1-xB_xM as defined in claim 43;

(b) impregnating the solution to a carrier powder; and

(c) calcining the carrier powder impregnated with the solution of step (a) to form the perovskite-type catalyst in the form of a dispersion.

51. The method of making a catalytic converter of claim 50, wherein the carrier powder is selected from a group consisting of titania, silica, gamma alumina, alpha alumina, ceria, zirconia, ceria-zirconia, and a mixture thereof.

52. The method of claim 45, wherein the bulk perovskite-type catalyst and the carrier powder is slurry deposited onto the support as a layer of washcoat.

53. The method of making a catalytic converter of claim 52 further comprising the steps of:

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

B;

M is the same as their ratio in the formula A_1-xB_xM as defined in claim 43;

(b) impregnating the solution onto the washcoat of the support, wherein the support is pre-coated with the carrier power and bulk perovskite-type catalyst by slurry deposition; and

(c) calcining the pre-coated support impregnated with the solution to form a perovskite-type metal oxide on the pre-coated support.

54. The method of making a catalytic converter of claim 53, wherein the perovskite-type metal oxide deposited on the pre-coated support may be the same or different from the bulk perovskite-type catalyst contained in the pre-coated support.

55. The method of claim 54, wherein the perovskite-type metal oxide has a formula Ln_0.5Sr_0.5Mn_0.98Pd_0.02O₃, and the bulk perovskite-type catalyst has a formula Ln_{0 8}Sr_0.2Mn_{0 9}O₃.

56. The method of making a catalytic converter of claim 55, wherein the carrier is a mixture of ceria-zirconia and gamma alumina powders.

57. The method of making a catalytic converter of claim 52 further comprising the steps of:

(a) forming a homogeneous solution of a salt of a catalyst;

(b) impregnating the solution onto washcoat of the support; and

(c) calcining the pre-coated support impregnated with the solution for forming the catalyst on the support.

58. The method of making a catalytic converter of claim 57, wherein the solution contains single base or noble metals or a binary mixture thereof.

59. The method of making a catalytic converter of claim 58, 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, 80-83.

60. The method of making a catalytic converter of claim 58, wherein the noble metal is selected from a group consisting of elements with atomic numbers 44, 45, 46, 47, 76, 77, 78 and 79.

61. The method of making a catalytic converter of claim 58, wherein the binary mixture is a mixture of two single bases, a single base and a noble metal, or two noble metals.

62. The method of making a catalytic converter of claim 58, wherein the catalyst solution has the cation ratio Sr₂Pd_{0 1}.

63. The method of claim 43, wherein the support is in the form of beads or pellets.

64. The method of claim 63, wherein the support is made of a carrier material.

65. The method of claim 64, wherein the carrier material is selected from a group consisting of aluminas, titania, silica, and the like.

66. The method of claim 43, wherein the support structure is a honeycomb support.

67. The method of claim 66, wherein the honeycomb support is a ceramic honeycomb support.

68. The method of claim 66, wherein the honeycomb support is a metal honeycomb support.

70. The method of claim 69, wherein the carrier powder is selected from a group consisting of titania, silica, gamma-alumina, alpha-alumina, ceria, zirconia, ceria-zirconia, ceria doped with rare-earths, alkaline earths, and transition metals.

71. The method of claim 69, wherein the washcoat comprises ceria-zirconia and gamma-alumina in ratios ranging from one part ceria-zirconia to ten parts gamma-alumina (by weight) to washcoats containing only ceria-zirconia.

69. A method of making a catalytic converter comprising the steps of:

(a) providing a carrier powder;

(b) providing a support;

(c) depositing the carrier powder to the surface of the support for forming a washcoat on the surface of the surport;

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

B;

M is the same as their ratio in the formula A_1-xB_xM;

wherein

A is a mixture of elements originally in the form of a single phase mixed lanthanide 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 22 to 30, 40 to 51, and 73 to 80;

x is a number defined by 0≦

x<

0.5;

(e) impregnating the solution onto the washcoat of the support, and

(f) calcining the pre-coated support impregnated with the solution for forming a perovskite-type metal oxide on the pre-coated support.