DIESEL OXIDATION CATALYST AND USE THEREOF IN DIESEL AND ADVANCED COMBUSTION DIESEL ENGINE SYSTEMS

• US 20100183490A1
• Filed: 01/14/2010
• Published: 07/22/2010
• Est. Priority Date: 01/16/2009
• Status: Active Grant

• Current Assignee: BASF Corporation (BASF SE)
• Original Assignee: BASF Catalysts LLC (BASF SE)
• Inventors: Hoke, Jeffrey B., Dettling, Joseph C.
• Granted Patent: US 9,440,192 B2
• Time in Patent Office: Days
• US Class Current: 423/213.500
• CPC Class Codes: B01D 2255/1021 Platinum
• CPC Class Codes: B01D 2255/1023 Palladium
• CPC Class Codes: B01D 2255/206 Rare earth metals
• CPC Class Codes: B01D 2255/20707 Titanium
• CPC Class Codes: B01D 2255/20715 Zirconium
• CPC Class Codes: B01D 2255/2092 Aluminium
• CPC Class Codes: B01D 2255/30 Silica
• CPC Class Codes: B01D 2255/407 Zr-Ce mixed oxides
• CPC Class Codes: B01D 2255/502 Beta zeolites
• CPC Class Codes: B01D 2255/504 ZSM 5 zeolites
• CPC Class Codes: B01D 2255/9022 Two layers
• CPC Class Codes: B01D 2255/9032 Two zones
• CPC Class Codes: B01D 2255/904 Multiple catalysts
• CPC Class Codes: B01D 2255/915 Catalyst supported on particulate filters
• CPC Class Codes: B01D 2258/012 Diesel engines and lean burn gasoline engines
• CPC Class Codes: B01D 2258/014 Stoichiometric gasoline engines
• CPC Class Codes: B01D 53/945 characterised by a specific catalyst
• CPC Class Codes: B01D 53/9454 characterised by a specific device
• CPC Class Codes: B01D 53/9477 with catalysts positioned on separate bricks, e.g. exhaust systems
• CPC Class Codes: B01J 23/63 with rare earths or actinides
• CPC Class Codes: B01J 29/7415 : Zeolite Beta
• CPC Class Codes: B01J 35/19 : Catalysts containing parts with different compositions
• 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 37/0244 : Coatings comprising several layers
• CPC Class Codes: B01J 37/0246 : Coatings comprising a zeolite
• CPC Class Codes: F01N 2250/02 : filtering and catalytic conversion
• CPC Class Codes: F01N 2510/063 : zeolites
• CPC Class Codes: F01N 2510/0682 : having a discontinuous, uneven or partially overlapping coating of catalytic material, e.g. higher amount of material upstream than downstream or vice versa
• CPC Class Codes: F01N 2510/0684 : having more than one coating layer, e.g. multi-layered coatings
• CPC Class Codes: F01N 2570/10 : Carbon or carbon oxides
• CPC Class Codes: F01N 2570/12 : Hydrocarbons
• CPC Class Codes: F01N 3/021 : by means of filters
• CPC Class Codes: F01N 3/035 : with catalytic reactors , e.g. catalysed diesel particulate filters
• CPC Class Codes: F01N 3/10 : by thermal or catalytic conversion of noxious components of exhaust by using other chemical processes, chemical aspects of catalytic conversion, e.g. using specified catalysts, B01D53/34
• CPC Class Codes: F01N 3/103 : Oxidation catalysts for HC and CO only
• CPC Class Codes: F01N 3/2066 : Selective catalytic reduction [SCR]
• CPC Class Codes: F01N 3/2807 : Metal other than sintered metal F01N3/2832 and F01N3/2835 take precedence
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies

Abstract

An oxidation catalyst composite, methods and systems for the treatment of exhaust gas emissions from an advanced combustion engine, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO) and the reduction of nitrogen oxides (NOx) from a diesel engine and an advanced combustion diesel engine are disclosed. More particularly, washcoat compositions are disclosed comprising at least two washcoat layers, a first washcoat comprising a palladium component and a first support containing cerium and a second washcoat containing platinum and one or more molecular sieves.

Claims

1. An oxidation catalyst composite for abatement of exhaust gas emissions from an engine comprising:

a carrier substrate having a length, an inlet end and an outlet end, a diesel oxidation catalyst catalytic material on the carrier, the diesel oxidation catalyst catalytic material including a first washcoat layer and a second washcoat layer,

the first washcoat layer comprising a palladium (Pd) component and first refractory metal oxide support including cerium, the first washcoat layer being substantially free of a molecular sieve; and

the second washcoat layer comprising a second refractory oxide support, a platinum component and a molecular sieve, the second washcoat layer being substantially free of palladium.

2. The oxidation catalyst composite of claim 1, wherein the first refractory metal oxide support further comprises one or more of alumina, silica, zirconia, titania and combinations thereof and the second refractory oxide support comprises one or more of alumina, silica, zirconia, titania and combinations thereof.

3. The oxidation catalyst composite of claim 1, wherein the molecular sieve comprises a zeolite.

4. The oxidation catalyst composite of claim 1, further comprising an undercoat layer containing substantially no precious group metal component.

5. The oxidation catalyst composite of claim 1, wherein the first washcoat extends over the entire length of the substrate and the second washcoat completely overlaps the first washcoat.

6. The oxidation catalyst composite of claim 1, wherein the first washcoat layer is upstream from and adjacent to the second washcoat layer along the length of the carrier substrate.

7. The oxidation catalyst composite of claim 6, wherein the first washcoat layer extends from the inlet end along about 5% to 95% of the length of the substrate and the second washcoat layer extends from the outlet along about 5% to 95% of the length of the substrate.

8. The oxidation catalyst composite of claim 7, wherein the first layer at least partially overlaps the second washcoat layer.

9. The oxidation catalyst composite of claim 7, wherein the second washcoat layer at least partially overlaps the first washcoat layer.

10. The oxidation catalyst composite of claim 1, wherein the platinum and palladium are present in a platinum to palladium ratio of from about 1:

10 to about 10;

1.

11. The oxidation catalyst composite of claim 1, wherein the platinum and palladium are present in a platinum to palladium ratio of from about 1:

4 to about 2;

1.

12. The oxidation catalyst composite of claim 1, wherein the first washcoat further comprises a second platinum component.

13. The oxidation catalyst composite of claim 12, further comprising an undercoat layer containing substantially no precious group metal component.

14. The oxidation catalyst composite of claim 1, wherein the catalyst is effective to oxidize HC and CO emitted from an advanced combustion diesel engine, including a methane component, the first layer being active for oxidizing CO and HCs under high emission and low temperature conditions associated with advanced combustion diesel engine operation.

15. The oxidation catalyst composite of claim 1, wherein the first support comprises ceria and the molecular sieve comprises a zeolite selected from beta-zeolite, ZSM-5, zeolite-Y or combinations thereof.

16. The oxidation catalyst composite of claim 1, wherein the total loading of the platinum and palladium is in the range of about 30 g/ft³ and 210 g/ft³.

17. A method for treating a diesel exhaust gas stream or an advanced combustion diesel exhaust gas stream comprising contacting the exhaust gas stream with a diesel oxidation catalyst composite of claim 1.

18. The method of claim 17, further comprising directing the diesel exhaust gas stream to a soot filter located downstream of the diesel oxidation catalyst composite.

19. The method of claim 18, further comprising directing diesel exhaust gas to a selective catalytic reduction (SCR) catalytic article located downstream of the catalyzed soot filter (CSF).

20. An diesel engine exhaust gas treatment system comprising:

a catalyst composite of claim 1; and

one or more of a soot filter, a catalyzed soot filter, a selective catalytic reduction (SCR) catalytic article and a NO_x storage and reduction (NSR) catalytic article.