Co slip catalyst and method of using

Patent metadata

Field	Value
Publication number	US-9266064-B2
Application number	US-201414471683-A
Country	US
Kind code	B2
Filing date	Aug 28, 2014
Priority date	Aug 28, 2013
Publication date	Feb 23, 2016
Grant date	Feb 23, 2016

Abstract

A CO slip catalyst, for treating an exhaust gas from a lean burn internal combustion engine, is disclosed. The CO slip catalyst comprises palladium and a ceria-containing material. The invention also includes a method for oxidizing excess CO in an exhaust gas, wherein the excess CO results from the periodic contact of an upstream catalyst under rich exhaust conditions. The method comprises contacting the excess CO in the exhaust gas with a CO slip catalyst at a temperature in the range of 100 to 700° C.

First claim

We claim:

1. A method of oxidizing excess CO in an exhaust gas from a lean burn internal combustion engine, wherein the excess CO results from the periodic contact of an upstream catalyst under rich exhaust conditions, said method comprising contacting the excess CO in the exhaust gas with a CO slip catalyst at a temperature in the range of 100 to 700° C., wherein the CO slip catalyst comprises palladium and a ceria-containing material, and the CO slip catalyst comprises 0.5 to 5 weight percent palladium.

2. The method of claim 1 , wherein the ceria-containing material comprises ceria, ceria-zirconia, ceria-zirconia-alumina, and mixtures thereof.

3. The method of claim 2 , wherein the ceria-containing material comprises ceria.

4. The method of claim 1 , further comprising one or more alkali or alkaline earth metals.

5. The method of claim 1 , further comprising one or more inorganic oxide binders selected from the group consisting of alumina, silica, titania, zirconia, magnesia, niobia, tantalum oxide, molybdenum oxide, tungsten oxide, and mixed oxides of any two or more thereof.

6. The method of claim 1 , wherein the CO slip catalyst is coated on a substrate.

Assignees

• Johnson Matthey Plc

Inventors

• Weigert Erich Conlan
• Mulla Shadab Sharif
• Ballinger Todd Howard
• Rieck Jeffery Scott
• Cox Julian Peter
• Chen Hai-Ying

Classifications

• Y02A50/20

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

• F01N2510/06

  for exhaust purification, e.g. catalytic reaction · CPC title

• F01N2370/02

  used in catalytic reactors · CPC title

• B01D2255/904

  Multiple catalysts · CPC title

• B01D2255/20715

  Zirconium · CPC title