Three-way catalytic converter using nanoparticles

• US 9,533,299 B2
• Filed: 09/04/2015
• Issued: 01/03/2017
• Est. Priority Date: 11/21/2012
• Status: Active Grant

• Current Assignee: Umicore AG & Company KG (Umicore S.A.)
• Original Assignee: SDC Materials,Inc.
• Inventors: Qi, Xiwang, Biberger, Maximilian A.
• Primary Examiner(s): Nguyen, Cam N.
• Application Number:
  US14/846,495
• Publication Number:
  US 20160074855A1
• Time in Patent Office: 487 Days
• Field of Search: 502/304, 502/327, 502/328, 502332-334, 502/339, 502/349, 502/355, 502/415, 502/439, 502/527.12, 502/527.13
• US Class Current: 1/1
• CPC Class Codes: B01D 2255/1021 Platinum
• CPC Class Codes: B01D 2255/1023 Palladium
• CPC Class Codes: B01D 2255/1025 Rhodium
• CPC Class Codes: B01D 2255/2042 Barium
• CPC Class Codes: B01D 2255/2065 Cerium
• CPC Class Codes: B01D 2255/20715 Zirconium
• CPC Class Codes: B01D 2255/407 Zr-Ce mixed oxides
• CPC Class Codes: B01D 2255/9022 Two layers
• CPC Class Codes: B01D 2255/908 O2-storage component incorporated in the catalyst
• CPC Class Codes: B01D 2255/91 NOx-storage component incorporated in the catalyst
• CPC Class Codes: B01D 2255/9202 Linear dimensions
• CPC Class Codes: B01D 2258/014 Stoichiometric gasoline engines
• CPC Class Codes: B01D 53/00 Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols, recovery of volatile solvents by condensation B01D5/00; sublimation B01D7/00; cold traps, cold baffles B01D8/00; working-up undefined gaseous mixtures obtained by cracking hydrocarbon oils C10G70/00; cleaning coal gas C10K; working-up of natural gas, or synthetic natural gas, C10L3/10; separation of difficult-to-condense gases or air by liquefaction F25J; for investigating materials G01N30/00
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01J 21/04 Alumina
• CPC Class Codes: B01J 21/066 Zirconium or hafnium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 23/42 Platinum
• CPC Class Codes: B01J 23/44 Palladium
• CPC Class Codes: B01J 23/464 Rhodium
• CPC Class Codes: B01J 23/63 with rare earths or actinides
• CPC Class Codes: B01J 35/19 : Catalysts containing parts with different compositions
• CPC Class Codes: B01J 35/23 : in a colloidal state
• CPC Class Codes: B01J 35/40 : characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/56 : Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: B01J 37/0045 : Drying a slurry, e.g. spray drying
• CPC Class Codes: B01J 37/0228 : in several steps
• CPC Class Codes: B01J 37/0244 : Coatings comprising several layers
• CPC Class Codes: B01J 37/08 : Heat treatment B01J37/0009, B01J37/0018 take precedence
• CPC Class Codes: B01J 37/349 : making use of flames, plasmas or lasers
• CPC Class Codes: F01N 2510/068 : characterised by the distribution of the catalytic coatings
• CPC Class Codes: F01N 3/0842 : Nitrogen oxides
• CPC Class Codes: F01N 3/0864 : Oxygen
• CPC Class Codes: F01N 3/101 : Three-way catalysts
• CPC Class Codes: Y02A 50/20 : Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y10T 428/24149 : Honeycomb-like
• CPC Class Codes: Y10T 428/25 : Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

The present disclosure relates to a substrate comprising nanomaterials for treatment of gases, washcoats for use in preparing such a substrate, and methods of preparation of the nanomaterials and the substrate comprising the nanomaterials. More specifically, the present disclosure relates to a substrate comprising nanomaterial for three-way catalytic converters for treatment of exhaust gases.

Claims

1. A method of forming a coated substrate, the method comprising:

a) coating a substrate with a washcoat composition comprising oxidative catalytically active particles;

wherein the oxidative catalytically active particles comprise oxidative composite nanoparticles bonded to micron-sized carrier particles where the micron-sized carrier particles comprise metal oxide, and the oxidative composite nanoparticles comprise a first support nanoparticle comprising metal oxide and one or more oxidative catalyst nanoparticles comprising a first platinum group metal; and

b) coating the substrate with a washcoat composition comprising reductive catalytically active particles;

wherein the reductive catalytically active particles comprise reductive composite nanoparticles bonded to micron-sized carrier particles where the micron-sized carrier particles comprise metal oxide, and the reductive composite nanoparticles comprise a second support nanoparticle comprising metal oxide and one or more reductive catalyst nanoparticles comprising a second platinum group metal.

2. The method of claim 1, wherein the oxidative catalyst nanoparticles comprise palladium.

3. The method of claim 1, wherein the oxidative catalyst nanoparticles comprise platinum.

4. The method of claim 1, wherein the oxidative catalyst nanoparticles comprise a mixture of platinum and palladium.

5. The method of claim 1, wherein the first support nanoparticle comprises aluminum oxide.

6. The method of claim 1, wherein the micron-sized carrier particles of the oxidative catalytically active particles comprise aluminum oxide.

7. The method of claim 1, wherein the reductive catalyst nanoparticles comprise rhodium.

8. The method of claim 1, wherein the micron-sized carrier particles of the reductive catalytically active particles comprise cerium zirconium oxide.

9. The method of claim 1, wherein either or both washcoat layers further comprise an oxygen storage component.

10. The method of claim 9, wherein the oxygen storage component comprises cerium zirconium oxide or cerium oxide.

11. The method of claim 1, further comprising drying and calcining the substrate after each coating.

12. The method of claim 1, wherein the washcoat layers further comprise boehmite.

13. A method of forming a coated substrate, the method comprising:

a) coating a substrate with a washcoat composition comprising oxidative catalytically active particles and reductive catalytically active particles;

wherein the oxidative catalytically active particles comprise oxidative composite nanoparticles bonded to micron-sized carrier particles where the micron-sized carrier particles comprise metal oxide, and the oxidative composite nanoparticles comprise a first support nanoparticle comprising metal oxide and one or more oxidative catalyst nanoparticles comprising a first platinum group metal; and

the reductive catalytically active particles comprise reductive composite nanoparticles bonded to micron-sized carrier particles where the micron-sized carrier particles comprise metal oxide, and the reductive composite nanoparticles comprise a second support nanoparticle comprising metal oxide and one or more reductive catalyst nanoparticles comprising a second platinum group metal.

14. The method of claim 13, wherein the oxidative catalyst nanoparticles comprise palladium.

15. The method of claim 13, wherein the oxidative catalyst nanoparticles comprise platinum.

16. The method of claim 13, wherein the oxidative catalyst nanoparticles comprise a mixture of platinum and palladium.

17. The method of claim 13, wherein the first support nanoparticle comprises aluminum oxide.

18. The method of claim 13, wherein the micron-sized carrier particles of the oxidative catalytically active particles comprise aluminum oxide.

19. The method of claim 13, wherein the reductive catalyst nanoparticles comprise rhodium.

20. The method of claim 13, wherein the micron-sized carrier particles of the reductive catalytically active particles comprise cerium zirconium oxide.

21. The method of claim 13, wherein the washcoat layer further comprises an oxygen storage component.

22. The method of claim 21, wherein the oxygen storage component comprises cerium zirconium oxide or cerium oxide.

23. The method of claim 13, further comprising drying and calcining the substrate after the coating.

24. The method of claim 13, wherein the washcoat layer further comprises boehmite.