System and methods for using synergized PGM as a three-way catalyst

Patent metadata

Field	Value
Publication number	US-9511355-B2
Application number	US-201314090861-A
Country	US
Kind code	B2
Filing date	Nov 26, 2013
Priority date	Nov 26, 2013
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

Synergies resulting from combinations of catalyst systems including Copper-Manganese material compositions and PGM catalysts are disclosed. Variations of catalyst system configurations are tested to determine most effective material composition, formulation, and configuration for an optimal synergized PGM (SPGM) catalyst system. The synergistic effect of the selected SPGM catalyst system is determined under steady state and oscillating test conditions, from which the optimal NO/CO cross over R-value indicates enhanced catalytic behavior of the selected SPGM catalyst system as compared with current PGM catalysts for TWC applications. According to principles in the present disclosure, application of Pd on alumina-based support as overcoat and Cu—Mn spinel structure supported on Nb 2 O 5 —ZrO 2 as washcoat on suitable ceramic substrate, produce higher catalytic activity, efficiency, and better performance in TWC condition, especially under lean condition, than commercial PGM catalysts.

First claim

What is claimed is:

1. A catalyst system, comprising:
at least one substrate;
at least one washcoat comprising at least one oxygen storage material further comprising Cu—Mn spinel having a niobium-zirconia support oxide; and
at least one overcoat comprising at least one platinum group metal catalyst and Al 2 O 3 .

2. The catalyst system of claim 1 , wherein the Cu—Mn spinel comprises CuMn 2 O 4 .

3. The catalyst system of claim 1 , wherein the Cu—Mn spinel is stoichiometric.

4. The catalyst system of claim 1 , wherein the niobium-zirconia support oxide comprises Nb 2 O 5 —ZrO 2 .

5. The catalyst system of claim 1 , further comprising at least one impregnation layer.

6. The catalyst of claim 1 , wherein the at least one substrate comprises a ceramic.

7. The catalyst of claim 1 , wherein NO is reduced under lean exhaust conditions.

8. The catalyst of claim 1 , wherein CO is reduced under lean exhaust conditions.

9. The catalyst of claim 1 , wherein NO is reduced by greater than 95% under lean exhaust conditions.

10. The catalyst of claim 1 , wherein the reduction of NO is improved over a catalyst system comprising at least one platinum group metal catalyst and no Cu—Mn spinel.

11. A catalyst system, comprising:
at least one substrate;
at least one washcoat comprising at least one platinum group metal catalyst and Al 2 O 3 ; and
at least one overcoat comprising at least one oxygen storage material further comprising Cu—Mn spinel having a niobium-zirconia support oxide.

12. The catalyst system of claim 11 , wherein the Cu—Mn spinel comprises CuMn 2 O 4 .

13. The catalyst system of claim 11 , wherein the Cu—Mn spinel is stoichiometric.

14. The catalyst system of claim 11 , wherein the niobium-zirconia support oxide comprises Nb 2 O 5 —ZrO 2 .

15. The catalyst system of claim 11 , further comprising at least one impregnation layer.

16. The catalyst of claim 11 , wherein the at least one substrate comprises a ceramic.

17. The catalyst of claim 11 , wherein NO is reduced under lean exhaust conditions.

18. The catalyst of claim 11 , wherein CO is reduced under lean exhaust conditions.

19. The catalyst of claim 11 , wherein the reduction of NO is improved over a catalyst system comprising at least one platinum group metal catalyst and no Cu—Mn spinel.

20. A catalyst system, comprising:
at least one substrate comprising ceramics;
at least one washcoat comprising Al 2 O 3 ;
at least one overcoat comprising at least one oxygen storage material further comprising Cu—Mn spinel having a niobium-zirconia support oxide; and
at least one impregnation layer comprising at least one platinum group metal catalyst;
wherein the at least one platinum group metal catalyst comprises palladium.

Assignees

• Clean Diesel Tech Inc
• Clean Diesel Tech Inc (Cdti)

Inventors

• Nazarpoor Zahra
• Golden Stephen J

Classifications

• B01D2255/1021

  Platinum · CPC title

• B01J2523/00

  Constitutive chemical elements of heterogeneous catalysts · CPC title

• B01D2255/405

  Spinels · CPC title

• B01D2258/012

  Diesel engines and lean burn gasoline engines · CPC title

• B01D53/945

  characterised by a specific catalyst · CPC title