Manganese-Containing Diesel Oxidation Catalyst

Patent metadata

Field	Value
Publication number	US-2021069684-A1
Application number	US-202016953533-A
Country	US
Kind code	A1
Filing date	Nov 20, 2020
Priority date	Dec 16, 2013
Publication date	Mar 11, 2021
Grant date	—

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

1 . An oxidation catalyst composite for 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, Pt, and a first refractory metal oxide support containing Mn; 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 the range of about 10:1 to 1:10; and a third wash coat comprising palladium and a rare earth oxide component, the third washcoat being substantially free of platinum; wherein the oxidation catalyst composite is effective to abate hydrocarbon and carbon monoxide, and to oxidize NO to NO 2 in the lean burn engine exhaust.

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

3 . The oxidation catalyst composite of claim 1 , wherein the first wash coat is substantially free of palladium.

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

5 . The oxidation catalyst composite of claim 1 , wherein the Mn content of the first washcoat is in the range of 0.1% to 20% by weight.

6 . (canceled)

7 . The oxidation catalyst composite of claim 5 , wherein the Mn is present in a form selected from the group consisting of a Mn-containing solid solution with the refractory metal oxide, surface dispersed Mn on the refractory metal oxide by impregnation and discrete manganese oxide particles on the refractory metal oxide particles.

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

9 . (canceled)

10 . (canceled)

11 . (canceled)

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

13 . (canceled)

14 . 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.

15 . 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.

16 . (canceled)

17 . (canceled)

18 . 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.

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

20 . (canceled)

21 . (canceled)

22 . (canceled)

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

25 . (canceled)

26 . (canceled)

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

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

29 . The method of claim 28 , further comprising passing the exhaust gas stream to an SCR catalyst composition immediately downstream from the oxidation catalyst.

30 . (canceled)

31 . 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 an SCR catalyst located downstream from the oxidation catalyst.

32 . The system of claim 31 , wherein the SCR catalyst is coated onto the catalyzed soot filter.

33 . The system of claim 31 , wherein the SCR catalyst is on a 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