An automotive catalytic converter includes a three-way catalyst having Rh as the only precious metal configured as a front zone and a three-way catalyst having a mixture of Rh and Pd, Pt, or both configured as a rear zone, such that an exhaust gas from an internal combustion engine passes through the front zone before passing through the rear zone to minimize sulfur poisoning of the catalytic converter.

One or more embodiments relates to a method of catalytically converting a reactant gas mixture for pollution abatement of products of hydrocarbon fuel combustion. The method provides substituted mixed-metal oxides where catalytically active metals are substituted within the crystal lattice to create an active and well dispersed metal catalyst available to convert the reactant gas mixture. Embodiments may be used with gasoline and diesel fueled internal combustion engine exhaust, although specific embodiments may differ somewhat for each.

One or more embodiments relates to a method of catalytically converting a reactant gas mixture for pollution abatement of products of hydrocarbon fuel combustion. The method provides substituted mixed-metal oxides where catalytically active metals are substituted within the crystal lattice to create an active and well dispersed metal catalyst available to convert the reactant gas mixture. Embodiments may be used with gasoline and diesel fueled internal combustion engine exhaust, although specific embodiments may differ somewhat for each.

Catalyst compositions, articles, systems and methods related to a three-way-catalyst composition comprising alumina doped with a transition metal.

Disclosed is a system for integrally treating a composite waste gas including nitrogen oxides (NO.sub.x and N.sub.2O), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and perfluorinated compounds (PFCs). The system includes a first wet processor configured to wash and adsorb dust including gases, SO.sub.x, and ash dissolved in water, a decomposing reactor configured to receive waste gas processed in the first wet processor and process nitrogen oxides (NO.sub.x and N.sub.2O), fluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and perfluorinated compounds (PFCs) in the waste gas, and a second wet processor configured to receive the waste gas processed in the decomposing reactor and wash and adsorb the received waste gas. The system can efficiently treat a large amount of composite waste gas.

An exhaust gas purification device which has improved exhaust gas purification performance. An exhaust gas purification device which includes a first catalyst layer that contains: a Pd-supporting catalyst which is obtained by having alumina carrier particles support Pd; a first Rh-supporting catalyst which is obtained by having first ceria-zirconia carrier particles support Rh; and second ceria-zirconia carrier particles. This exhaust gas purification device is configured such that: the ceria concentration in the first ceria-zirconia carrier particles is 30 wt % or less; and the amount of ceria in the second ceria-zirconia carrier particles is larger than the amount of ceria in the first ceria-zirconia carrier particles.

A lean NO.sub.x trap catalyst and its use in an emission treatment system for internal combustion engines is disclosed. The lean NO.sub.x trap catalyst comprises a first layer, a second layer, and a third layer.

A lean NO.sub.x trap catalyst and its use in an emission treatment system for internal combustion engines is disclosed. The lean NO.sub.x trap catalyst comprises a first layer, a second layer, and a third layer.

An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine comprising a catalytic region and a substrate, wherein the catalytic region comprises a catalytic material comprising: a copper (Cu) component; a platinum group metal (PGM) selected from the group consisting of (i) platinum (Pt), (ii) palladium (Pd) and (iii) platinum (Pt) and palladium (Pd); and a support material, which is a refractory oxide comprising alumina; wherein the platinum group metal (PGM) and the copper (Cu) component is each supported on the support material.

This oxidation catalyst for diesel engines is divided into an upstream-side catalyst layer and a downstream-side inner catalyst layer in the flow direction of the exhaust gas, and a downstream-side outer catalyst layer is additionally formed so as to cover the surface of the downstream-side inner catalyst layer. The upstream-side catalyst layer and the downstream-side inner catalyst layer contain Pd, and the downstream-side outer catalyst layer contains Pt. The amounts of Pt and Pd contained in the upstream-side catalyst layer and the amounts of Pt and Pd contained in the downstream-side inner catalyst layer are constantly set to certain values, while the amount of Pt contained in the downstream-side outer catalyst layer is set to a value which enables the oxidation efficiency to be at a predetermined value or higher.