Manganese-containing diesel oxidation catalyst

Patent metadata

Field	Value
Publication number	US-11896962-B2
Application number	US-202016953533-A
Country	US
Kind code	B2
Filing date	Nov 20, 2020
Priority date	Dec 16, 2013
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

An oxidation catalyst composite, methods, and systems for the treatment of exhaust gas emissions from a diesel engine are described. More particularly, an oxidation catalyst composite including a first washcoat comprising a zeolite, Pt, and first refractory metal oxide support containing manganese, a second washcoat comprising a second refractory metal oxide support, a Pt component and a Pd component, and a third washcoat comprising palladium and a rare earth oxide component is described.

First claim

What is claimed is:

1. An oxidation catalyst composite for an abatement of exhaust gas emissions from a lean burn engine comprising:
a carrier substrate having a length, an inlet end and an outlet end, an oxidation catalyst catalytic material on the carrier, the oxidation catalyst catalytic material comprising:
a first washcoat including a zeolite, platinum (Pt), and a first refractory metal oxide support containing a manganese (Mn), wherein the Mn is present either in a form of surface dispersed Mn on the first refractory metal oxide or in a form of discrete manganese oxide particles on the first refractory metal oxide support, wherein the Mn content of the first washcoat is in a range of 0.1% to 20% by weight and wherein the manganese is doped with Fe, Ni, Co, Cu, Ce, Sn, Ir, In, or a combination thereof;
a second washcoat including a second refractory metal oxide support, a platinum (Pt) component and a palladium (Pd) component in a ratio of Pt:Pd in a range of about 10:1 to 1:10; and
a third washcoat comprising palladium and a rare earth oxide component, the third washcoat being substantially free of a platinum;
wherein the oxidation catalyst composite is effective to abate hydrocarbon and carbon monoxide, and to oxidize nitrogen monoxide (NO) to nitrogen dioxide (NO 2 ) in the lean burn engine exhaust.

2. The oxidation catalyst composite of claim 1 , wherein the first washcoat further optionally comprises a palladium component, and the Pt:Pd ratio of the first washcoat is in a range of 1:0 to 10:1.

3. The oxidation catalyst composite of claim 2 , wherein the palladium component is present in an amount in a range of about 0.1 g/ft 3 to about 10 g/ft 3 .

4. The oxidation catalyst composite of claim 1 , wherein the first washcoat is substantially free of a palladium.

5. The oxidation catalyst composite of claim 1 , wherein the Mn is derived from a soluble Mn species or from bulk Mn oxides.

6. The oxidation catalyst composite of claim 1 , wherein the first washcoat comprises the Pt component in an amount in a range of about 10 g/ft 3 to 100 g/ft 3 .

7. The oxidation catalyst composite of claim 1 , wherein the first washcoat comprises a hydrothermally stable zeolite in the form of 6 to 12 member ring structures selected from ZSM-5, beta, mordenite, Y zeolite, chabazite, ferrierite, or combinations thereof.

8. The oxidation catalyst composite of claim 1 , wherein the second refractory metal oxide support comprises an oxide of alumina, silica, zirconia, titania, ceria, or combinations thereof.

9. The oxidation catalyst composite of claim 1 , wherein the first washcoat is substantially free of barium, and the second washcoat is substantially free of zeolite.

10. The oxidation catalyst composite of claim 1 , wherein the third washcoat comprises the rare earth oxide component selected from Ce, Nd, Y, Pr, Zr, La, or combinations thereof.

11. The oxidation catalyst composite of claim 1 , wherein the first, second and third washcoats of the oxidation catalyst can be layered or zoned on a flow-through monolith substrate in any combination.

12. The oxidation catalyst composite of claim 1 , wherein the carrier substrate comprises a flow-through monolith.

13. A method for treating a diesel engine exhaust gas stream, the method comprising contacting the diesel exhaust gas stream with the oxidation catalyst composite of claim 1 .

14. The method of claim 13 , further comprising passing the diesel exhaust gas stream to a selective catalyst reduction (SCR) catalyst composition immediately downstream from the oxidation catalyst.

15. A system for treatment of a lean burn engine exhaust gas stream including hydrocarbons, carbon monoxide, and other exhaust components, the system comprising:
an exhaust conduit in fluid communication with the lean burn engine via an exhaust manifold;
the oxidation catalyst composite of claim 1 , wherein the carrier substrate is a flow through substrate; and
a catalyzed soot filter and a selective catalytic reduction (SCR) catalyst located downstream from the oxidation catalyst.

16. The system of claim 15 , wherein the SCR catalyst is coated onto the catalyzed soot filter.

17. The system of claim 15 , wherein the SCR catalyst is on the flow through substrate immediately downstream from the oxidation catalyst composite and the catalyzed soot filter is downstream from the SCR catalyst.

Assignees

• Basf Corp

Inventors

• Sung Shiang
• Roth Stanley A
• Dumbuya Karifala
• Stiebels Susanne
• Zabel Claudia
• Gerlach Olga
• Sundermann Andreas

Classifications

• B01J35/19

  Catalysts containing parts with different compositions · CPC title

• B01J37/0246

  Coatings comprising a zeolite · CPC title

• B01J37/0244

  Coatings comprising several layers · CPC title

• B01J29/076 Primary

  containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium · CPC title

• B01D53/945

  characterised by a specific catalyst · CPC title