Catalytic article and exhaust gas treatment systems

Patent metadata

Field	Value
Publication number	US-2021069688-A1
Application number	US-201816619861-A
Country	US
Kind code	A1
Filing date	Jun 8, 2018
Priority date	Jun 9, 2017
Publication date	Mar 11, 2021
Grant date	—

Abstract

The present invention relates to a catalytic article comprising a substrate having a catalyst composition disposed thereon, wherein the catalyst composition comprises a platinum group metal impregnated onto a porous support and a selective catalytic reduction catalyst, wherein the catalyst composition is substantially free of platinum; and wherein the catalytic article is effective in the abatement of nitrogen oxides (NOx) and hydrocarbons (HCs). The present invention further relates to exhaust gas treatment systems for treating an exhaust gas stream exiting a diesel engine.

First claim

1 . 1.A catalytic article comprising:
a substrate having a catalyst composition disposed thereon, wherein the catalyst composition comprises a platinum group metal impregnated onto a porous support and a selective catalytic reduction catalyst; wherein the catalyst composition is substantially free of platinum; and wherein the catalytic article is effective in the abatement of nitrogen oxides (NO x ) and hydrocarbons (HCs).

2 . The catalytic article of claim 1 , wherein the selective catalytic reduction catalyst comprises a mixed metal oxide component, wherein the mixed metal oxide component is selected from FeTiO 3 , FeAl 2 O 3 , MgTiO 3 , MgAlO 3 , MnO x /TiO 2 , CuTiO 3 , CeZrO 2 , TiZrO 2 , V 2 O 5 /TiO 2 , and mixtures thereof.

3 . The catalytic article of claim 1 , wherein the platinum group metal impregnated onto a porous support is palladium impregnated onto zirconia and the selective catalytic reduction catalyst comprises one or more of a mixed metal oxide and a zeolite comprising one or more of Cu and Fe.

4 . The catalytic article of claim 3 , wherein the selective catalytic reduction catalyst comprises a zeolite comprising Cu, preferably a zeolite having a framework structure type CHA.

5 . The catalytic article of claim 1 , wherein the catalyst composition comprises a first layer and a second layer, wherein the first layer comprises the selective catalytic reduction catalyst and the second layer comprises platinum group metal impregnated onto the porous support;
wherein the first layer is preferably disposed directly on the substrate and the second layer is disposed on top of the first layer; or wherein the second layer is preferably disposed directly on the substrate and the first layer is disposed on top of the second layer; or wherein the first layer and the second layer are preferably disposed directly on the substrate in a zoned configuration.

6 . The catalytic article of claim 1 , wherein the substrate has an inlet end, an outlet end and a substrate length extending from the inlet end to the outlet end of the substrate and comprises a plurality of passages defined by the internal walls of the substrate and wherein the catalyst composition comprises a first layer and a second layer, wherein the first layer comprises platinum group metal impregnated onto the porous support and the second layer comprises the selective catalytic reduction catalyst.

7 . The catalytic article of claim 6 , wherein the first layer comprises palladium impregnated onto one or more of zirconia and alumina.

8 . The catalytic article of claim 6 , wherein the selective catalytic reduction catalyst comprises a zeolite comprising Cu, preferably a zeolite having the structure type CHA.

9 . The catalytic article of claim 1 wherein the catalyst composition comprises, preferably consists of, a single layer.

10 . An emission treatment system for treatment of an exhaust gas stream, the emission treatment system comprising:
an engine producing an exhaust gas stream; the catalytic article according to claim 1 positioned downstream from the engine in fluid communication with the exhaust gas stream and adapted for the reduction of NOx and HCs within the exhaust stream to form a treated exhaust gas stream; and an injector adapted for the addition of a reductant to the exhaust gas stream upstream of the catalytic article.

11 . An exhaust gas treatment system for treating an exhaust gas stream leaving a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, wherein said exhaust gas treatment system comprises
the catalytic article according to claim 6 , the catalytic article having an inlet end and an outlet end; wherein the catalytic article is the first catalytic article of the exhaust gas treatment system downstream of the upstream end of the exhaust gas treatment system and wherein the inlet end of the catalytic article is arranged upstream of the outlet end of the catalytic article.

12 . An exhaust gas treatment system for treating an exhaust gas stream exiting a diesel engine, said exhaust gas treatment system having an upstream end for introducing said exhaust gas stream into said exhaust gas treatment system, wherein said exhaust gas treatment system comprises
(i) a first catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, wherein the coating comprises palladium supported on an oxidic material comprising zirconium and further comprises one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron; or a first catalyst having an inlet end and an outlet end and being the catalytic article according to claim 1 ; (ii) a second catalyst having an inlet end and an outlet end and comprising a coating disposed on a substrate, wherein the coating comprises a platinum group metal supported on an oxidic material and further comprises one or more of a vanadium oxide, a tungsten oxide and a zeolitic material comprising one or more of copper and iron; wherein the first catalyst according to (i) is the first catalyst of the exhaust gas treatment system downstream of the upstream end of the exhaust gas treatment system and wherein the inlet end of the first catalyst is arranged upstream of the outlet end of the first catalyst; wherein in the exhaust gas treatment system, the second catalyst according to (ii) is located downstream of the first catalyst according to (i) and wherein the inlet end of the second catalyst is arranged upstream of the outlet end of the second catalyst.

13 . The exhaust gas treatment system of claim 12 , wherein the coating of the first catalyst comprises palladium supported on an oxidic material comprising zirconium, wherein from 99 to 100 weight-% of the oxidic material consist of zirconium and oxygen, preferably zirconia, and comprises a zeolitic material comprising one or more of copper and iron.

14 . A catalyst for the selective catalytic reduction of NOx and for the oxidation of a hydrocarbon, comprising a coating disposed on a substrate, wherein the coating comprises
palladium supported on an oxidic material comprising zirconium, and further comprises one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein from 0 to 2 weight-% of the oxidic material consist of ceria and alumina.

15 . The catalyst of claim 14 , wherein from 90 to 100 weight-%, preferably from 95 to 100 weight-%, more preferably from 99 to 100 weight-% of the oxidic material comprised in the coating consist of zirconium and oxygen, preferably of zirconia.

16 . The catalyst of claim 14 , wherein the coating comprises a zeolitic material comprising one or more of copper and iron, wherein the zeolitic material has preferably a framework structure of the type CHA.

17 . A method for preparing a catalyst, preferably the first catalyst comprised in the exhaust gas treatment system according to claim 12 , comprising
(A) preparing a first mixture comprising palladium, an oxidic material comprising zirconium, and water, (B) preparing a second mixture comprising a solvent and one or more of a vanadium oxide and a zeolitic material comprising one or more of copper and iron, wherein the vanadium oxide is preferably supported on an oxidic material comprising one or more of titanium, silicon, and zirconium, more preferably an oxidic material comprising one or more of titanium and silicon, more preferably an oxidic material comprising one or more of titania and silica, more pref

Assignees

• Basf Corp

Inventors

• Patchett Joseph A
• Beard Kevin
• Huennekes Edgar Viktor
• Dorner Robert
• Hallstrom Kevin A
• Wille Ansgar
• Voss Kenneth E
• Kalwei Martin

Classifications

• Y02A50/20

  Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title

• B01J35/56

  Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths · CPC title

• B01J37/08

  Heat treatment {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• F01N13/16

  Selection of particular materials · CPC title