Back to results
US 5,130,109 AGranted
Catalyst composition containing segregated platinum and rhodium components
OwnerChung-Zong Waninventor
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
OwnerChung-Zong Waninventor
Estimating the term…
A catalyst composition suitable for three-way conversion of internal combustion engine, e.g., automobile gasoline engine, exhaust gases, includes a catalytic material disposed in two discrete coats on a carrier. The first coat includes a stabilized alumina support on which a first platinum catalytic component is dispersed and bulk ceria, and may also include bulk iron oxide, a metal oxide (such as bulk nickel oxide) which is effective for the suppression of hydrogen sulfide emissions, and one or both of baria and zirconia dispersed throughout the first coat as a thermal stabilizer. The second coat, which may comprise a top coat overlying the first coat, contains a co-formed (e.g., co-precipitated) rare earth oxide-zirconia support on which a first rhodium catalytic component is dispersed, and a second activated alumina support having a second platinum catalytic component dispersed thereon. The second coat may also include a second rhodium catalytic component, and optionally, a third platinum catalytic component, dispersed as an activated alumina support. The present invention also provides a method for treating engine exhaust gases by contacting the gases under conversion conditions with the catalyst composition.
A method for treating a gas containing noxious components comprising one or more of carbon monoxide, hydrocarbons and nitrogen oxides, by converting at least some of the noxious components to innocuous substances, the method comprising contacting the gas under conversion conditions with a catalyst composition comprising a carrier on which is disposed a catalytic material, the catalytic material comprising (i) a first coat carried on the carrier and comprising a first activated alumina support, a catalytically effective amount of a first platinum catalytic component dispersed on the alumina support, and a catalytically effective amount of bulk ceria and (ii) a second coat carried by the carrier and comprising a co-formed rare earth oxide-zirconia support, a catalytically effective amount of a first rhodium catalytic component dispersed on the co-formed zirconia support, and a catalytically effective amount of a second platinum catalytic component dispersed on the second alumina support.
A method for treating a gas containing noxious components comprising one or more of carbon monoxide, hydrocarbons and nitrogen oxides, by converting at least some of the noxious components to innocuous substances, the method comprising contacting the gas under conversion conditions with a catalyst composition comprising a carrier on which is disposed a catalytic material, the catalytic material comprising (i) a first coat carried on the carrier and comprising a first activated alumina support, a catalytically effective amount of a first platinum catalytic component dispersed on the alumina support, a catalytically effective amount of bulk ceria and of bulk iron oxide, a catalytically effective amount of bulk nickel oxide, and baria and zirconia dispersed throughout the first coat in an amount sufficient to stabilize the alumina and iron oxide against thermal degradation;
Dependencies are inferred from the claim text.