Thermally Stable Zero PGM Catalysts System for TWC Application

• US 20160121309A1
• Filed: 10/30/2014
• Published: 05/05/2016
• Est. Priority Date: 10/30/2014
• Status: Abandoned Application

• Current Assignee: Clean Diesel Technologies, Inc.
• Original Assignee: Clean Diesel Technologies, Inc.
• Inventors: Nazarpoor, Zahra, Golden, Stephen J.
• Application Number:
  US14/528,788
• Publication Number:
  US 20160121309A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2255/2061 Yttrium
• CPC Class Codes: B01D 2255/20715 Zirconium
• CPC Class Codes: B01D 2255/2073 Manganese
• CPC Class Codes: B01D 2255/20746 Cobalt
• CPC Class Codes: B01D 2255/20761 Copper
• CPC Class Codes: B01D 2255/2092 Aluminium
• CPC Class Codes: B01D 2255/402 Perovskites
• CPC Class Codes: B01D 2255/405 Spinels
• CPC Class Codes: B01D 2255/65 Catalysts not containing noble metals
• CPC Class Codes: B01D 2255/908 O2-storage component incorporated in the catalyst
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01D 53/9468 in different layers
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/005 Spinels
• CPC Class Codes: B01J 23/8892 Manganese
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/17 Copper
• CPC Class Codes: B01J 2523/31 Aluminium
• CPC Class Codes: B01J 2523/36 Yttrium
• CPC Class Codes: B01J 2523/3712 Cerium
• CPC Class Codes: B01J 2523/48 : Zirconium
• CPC Class Codes: B01J 2523/72 : Manganese
• CPC Class Codes: B01J 2523/845 : Cobalt
• CPC Class Codes: B01J 37/0242 : Coating followed by impregnation
• CPC Class Codes: B01J 37/0244 : Coatings comprising several layers
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

Effect of the type of material composition employed within overcoat in conjunction with ZPGM composition in impregnation layer on thermal stability and TWC performance of ZPGM catalyst systems is disclosed. Effect of aging temperature on thermal stability of disclosed ZPGM catalyst systems is also described. Testing of ZPGM catalyst samples including isothermal steady state sweep test condition and isothermal oscillating TWC test on disclosed ZPGM catalyst systems show that ZPGM catalyst system that includes combination of Cu₁Mn₂O₄ spinel and YMnO₃ perovskite exhibit higher level of thermal stability at temperature higher than temperatures registered for under floor application of TWC.

Claims

1. A zero platinum group metal (ZPGM) catalyst system comprising

a) an overcoat layer comprising a combination of a ZPGM with a doped zirconia, and

b) an impregnation layer comprising Cu—

Mn spinel.

2. The ZPGM catalyst system of claim 1, wherein the zirconia type support oxide is YMnO₃/doped ZrO₂.

3. The ZPGM catalyst system of claim 1, wherein Cu—

Mn spinel is according to the formula Cu_xMn_3-xO₄.

4. The ZPGM catalyst system of claim 3, wherein X is 1.

5. The ZPGM catalyst system of claim 3, wherein X is 1.5.

6. The ZPGM catalyst system of claim 1, wherein the Cu—

Mn spinel is CuCoMnO₄ spinel.

7. The ZPGM catalyst system of claim 1 further comprising an alumina-based washcoat layer coated on a ceramic substrate.

8. A zero platinum group metal (ZPGM) catalyst system comprising

a) an overcoat layer comprising Y—

Mn perovskite, and

b) an impregnation layer comprises Cu—

Mn spinel.

9. The ZPGM catalyst system of claim 8, wherein the Y—

Mn perovskite is perovskite YMnO₃.

10. The ZPGM catalyst system of claim 8, wherein Cu—

Mn spinel is according to the formula Cu_xMn_3-xO₄.

11. The ZPGM catalyst system of claim 10, wherein X is 1.

12. The ZPGM catalyst system of claim 10, wherein X is 1.5.

13. The ZPGM catalyst system of claim 8, wherein the Cu—

Mn spinel is CuCoMnO₄ spinel.

14. The ZPGM catalyst system of claim 8 further comprising an alumina-based washcoat layer coated on a ceramic substrate.

15. A method of producing an aged zero platinum group metal (ZPGM) catalyst system comprising aging the ZPGM catalyst system at a temperature of about 850°

C. to about 900°

C. for about 20 hours, wherein the ZPGM catalyst system comprises a) an overcoat layer comprising a combination of a ZPGM with a doped zirconia, and b) an impregnation layer comprising Cu—

Mn spinel.

16. The method of claim 15, wherein the zirconia type support oxide is YMnO₃/doped ZrO₂.

17. The method of claim 16, wherein the Cu—

Mn spinel is CuMn₂O₄ spinel.

18. A method of producing an aged zero platinum group metal (ZPGM) catalyst system comprising aging the ZPGM catalyst system at a temperature of about 850°

C. to about 900°

C. for about 20 hours, wherein the ZPGM catalyst system comprises a) the overcoat layer comprises Y—

Mn perovskite, and b) the impregnation layer comprises Cu—

Mn spinel.

19. The method of claim 18, wherein the Y—

Mn perovskite is perovskite YMnO₃.

20. The method of claim 18, wherein the Cu—

Mn spinel is CuMn₂O₄ spinel.