Cerium-Cobalt Spinel System as ZPGM Composition for DOC Applications

• US 20160263561A1
• Filed: 03/13/2015
• Published: 09/15/2016
• Est. Priority Date: 03/13/2015
• Status: Abandoned Application

• Current Assignee: Clean Diesel Technologies, Inc.
• Original Assignee: Clean Diesel Technologies, Inc.
• Inventors: Nazarpoor, Zahra, Golden, Stephen J.
• Application Number:
  US14/657,833
• Publication Number:
  US 20160263561A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2255/2065 Cerium
• CPC Class Codes: B01D 2255/20715 Zirconium
• CPC Class Codes: B01D 2255/20746 Cobalt
• CPC Class Codes: B01D 2255/20761 Copper
• CPC Class Codes: B01D 2255/405 Spinels
• CPC Class Codes: B01D 2255/9207 Specific surface
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01J 23/005 Spinels
• CPC Class Codes: B01J 23/83 with rare earths or actinides
• CPC Class Codes: B01J 23/894 with rare earths or actinides
• CPC Class Codes: B01J 35/00 Catalysts, in general, characterised by their form or physical properties
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

Variations of ZPGM catalyst material compositions including cerium-cobalt spinel oxide systems for ZPGM DOC applications are disclosed. The disclosed ZPGM catalyst compositions include Ce_xCo_3−xO₄ spinel and effect of adding copper to Ce-Co as Cu_xCe_1−xCo₂O₄ spinel systems supported on doped zirconia support oxide, which are produced by the incipient wetness (IW) methodology. ZPGM catalyst compositions are subjected to BET-surface area and XRD analyses to determine the thermal stability and spinel phase formation of supported spinal systems, respectively. DOC performance of ZPGM catalyst compositions is determined under steady state DOC light off test condition to verify/compare oxidation activity of disclosed spinel compositions, desirable and suitable for ZPGM catalyst materials in DOC applications.

Claims

1. A catalytic system, comprising:

a substrate;

a washcoat suitable for deposition on the substrate; and

an overcoat suitable for deposition on the substrate, the overcoat comprising a catalyst comprising a spinel having the general formula Ce_xCo<sub>3−

x</sub>Co₄, where x=0.2 to 1.5.

2. The system of claim 1, wherein the spinel has the formula CeCo₂O₄.

3. The system of claim 1, wherein the oxide powder comprising Ce_0.75Zr_0.5O₂.

4. The system of claim 1, wherein CO is oxidized by the catalyst.

5. The system of claim 1, wherein hydrocarbons are oxidized by the catalyst.

6. The system of claim 1, wherein NO oxidation occurs at about 275°

C.

7. The system of claim 1, wherein NO oxidation occurs between about 275°

C. and about 375°

C.

8. The system of claim 1, wherein NO conversion is greater than 60%.

9. The system of claim 1, wherein NO conversion is greater than 67%.

23. The catalyst of claim 1, wherein hydrocarbons are oxidized by the catalyst.

10. A catalyst, comprising:

a spinel having the general formula Ce_xCo<sub>3−

x</sub>O₄, where x=0.2 to 1.5.

11. The catalyst of claim 10, wherein the spinel has the formula CeCo₂O₄.

12. The catalyst of claim 10, wherein the oxide powder comprising Ce_0.75Zr_0.5O₂.

13. The catalyst of claim 10, wherein CO is oxidized by the catalyst.

14. The catalyst of claim 10, wherein hydrocarbons are oxidized by the catalyst.

15. The catalyst of claim 10, wherein NO oxidation occurs at about 275°

C.

16. The catalyst of claim 10, wherein NO oxidation occurs between about 275°

C. and about 375°

C.

17. The catalyst of claim 10, wherein NO conversion is greater than 60%.

18. The catalyst of claim 10, wherein NO conversion is greater than 67%.

19. A catalyst, comprising:

a spinel having the general formula Cu_xCe<sub>1−

x</sub>Co₂O₄, where x=0.01 to 0.99.

20. The catalyst of claim 19, wherein the spinel has the formula Cu_0.5Ce_0.5Co₂O₄.

21. The catalyst of claim 19, wherein the oxide powder comprising Ce_0.75Zr_0.5O₂.

22. The catalyst of claim 19, wherein CO is oxidized by the catalyst.

24. The catalyst of claim 19, wherein CO oxidation occurs at about 275°

C.

25. The catalyst of claim 19, wherein NO conversion is greater than 90%.