Formation and Stability of Cu-Mn Spinel Phase for ZPGM Catalyst Systems

• US 20140271388A1
• Filed: 12/05/2013
• Published: 09/18/2014
• Est. Priority Date: 03/15/2013
• Status: Abandoned Application

• Current Assignee: Clean Diesel Technologies, Inc.
• Original Assignee: CDTI
• Inventors: Nazarpoor, Zahra, Golden, Stephen J.
• Application Number:
  US14/098,070
• Publication Number:
  US 20140271388A1
• Time in Patent Office: Days
• US Class Current: 422/170
• CPC Class Codes: B01D 2255/2073 Manganese
• CPC Class Codes: B01D 2255/20761 Copper
• CPC Class Codes: B01D 2255/405 Spinels
• CPC Class Codes: B01D 2255/65 Catalysts not containing noble metals
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• 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 2523/48 Zirconium
• CPC Class Codes: B01J 2523/56 Niobium
• CPC Class Codes: B01J 2523/72 Manganese
• CPC Class Codes: B01J 37/03 Precipitation; Co-precipitation
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

Optimized Cu—Mn spinel compositions, with optimal spinel phase formation and phase stability properties, for a plurality of ZPGM catalysts in underfloor and closed-loop coupled catalyst applications are disclosed. Plurality of Cu—Mn spinel compositions are prepared with variations of molar ratios. Effect of calcination temperature is analyzed to determine spinel phase formation and phase stability, as well as the effect of calcination temperature on lattice parameter of spinel, as correlated to spinel phase formation and phase stability of optimal Cu—Mn spinel compositions disclosed. Disclosed Cu—Mn spinels with enhanced spinel phase formation and phase stability may be suitable for ZPGM catalyst systems used in a vast number of TWC applications.

Claims

1. A method of making a catalytic material, comprising:

providing at least one solution comprising Cu and Mn;

precipitating the at least one solution to form at least one precipitate;

heating the at least one precipitate; and

forming at least one catalyst having a general formula of Cu_xMn_3-xO₄;

wherein x is at least 0.5.

2. The method of claim 1, wherein x is less than 1.0.

3. The method of claim 1, wherein the heating is to at least 600°

C.

4. The method of claim 1, wherein the heating is to at least 1100°

C.

5. The method of claim 1, wherein the heating occurs for about 5 hours.

6. The method of claim 1, wherein the at least one catalyst comprises spinel structures.

7. The method of claim 1, wherein the at least one catalyst is substantially free of platinum group metals.

8. The method of claim 1, wherein the at least one catalyst is thermally stable.

9. The method of claim 1, wherein x is 1.5 and wherein the heating is to at least 700°

C.

10. The method of claim 1, further comprising applying the at least one catalyst to a substrate using the same temperature as said heating.

11. A catalyst comprising:

at least one oxygen storage material in the form of spinel having a general formula of Cu_0.5Mn_2.5O₄, wherein the spinel is stable at about 600°

C. to about 1100°

C.

12. A catalyst comprising:

at least one oxygen storage material in the form of spinel having a general formula of Cu_1.0Mn_2.0O₄, wherein the spinel is stable at about 600°

C. to about 1100°

C.

13. A catalyst system, comprising:

at least one close-couple converter; and

at least one underfloor converter;

wherein the underfloor converter comprises a catalyst system, comprising;

a substrate; and

a washcoat suitable for deposition on the substrate, comprising at least one oxygen storage material;

wherein the at least one oxygen storage material comprises Cu—

Mn spinel having a niobium-zirconia support oxide; and

wherein the Cu—

Mn spinel was formed using a method comprising;

providing at least one solution comprising Cu and Mn;

precipitating the at least one solution to form at least one precipitate;

heating the at least one precipitate; and

forming at least one catalyst having a general formula of Cu_xMn_3-xO₄;

wherein x is at least 0.5.

14. The method of claim 13, wherein x is less than 1.0.

15. The method of claim 13, wherein the heating is to at least 600°

C.

16. The method of claim 13, wherein the heating is to at least 1100°

C.

17. The method of claim 13, wherein the heating occurs for about 5 hours.

18. The method of claim 13, wherein the at least one catalyst comprises spinel structures.

19. The method of claim 13, wherein the at least one catalyst is substantially free of platinum group metals.

20. The method of claim 13, wherein the at least one catalyst is thermally stable.

21. The method of claim 13, wherein x is 1.5 and wherein the heating is to at least 700°

C.

22. The method of claim 13, further comprising applying the at least one catalyst to a substrate using the same temperature as said heating.