A method of manufacturing a catalyst article, the method comprising: providing a slurry comprising a support material, palladium ions, alkaline-earth-metal ions and an organic compound, wherein the organic compound comprises a functional group selected from a sulfo group (—SO.sub.3H), a sulfonyl group (—S(═O).sub.2—) and a sulfinyl group (—S(═O)—); disposing the slurry on a substrate; and heating the slurry to form nanoparticles of the palladium and nanoparticles of a sulfate of the alkaline earth metal on the support material.

A composite oxidation catalyst (18, 20) for use in an exhaust system for treating an exhaust gas produced by a vehicular compression ignition internal combustion engine (30) and upstream of a particulate matter filter (44, 50) in the exhaust system comprises a substrate (5) having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); and three or more catalyst washcoat zones (1, 2, 3; or 1, 2, 3, 4) arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1, wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end by a first end (19, 21) of a second catalyst washcoat zone (2) having a length L.sub.2, wherein L.sub.2<L, wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and two or more platinum group metal components supported thereon comprising both platinum and palladium at a weight ratio of platinum to palladium of ≥1; the second catalyst washcoat zone (2) comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a third catalyst washcoat zone (3) comprising a third refractory metal oxide support material and one or more platinum group metal components supported thereon is defined at a second end thereof by the second substrate end (O), wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per cubic foot of substrate volume (g/l) (g/ft.sup.3) is greater than a total platinum group metal loading in the second catalyst washcoat zone (2), wherein a total platinum group metal loading in the third catalyst washcoat zone (3) defined in grams of platinum group metal per cubic foot of substrate volume (g/l) (g/ft.sup.3) is less than the total platinum group metal loading in the second catalyst washcoat zone (2) and wherein the first catalyst washcoat zone (1) comprises one or more first alkaline earth metal components supported on the first refractory metal oxide support material.

A compression ignition internal combustion engine (30) for a heavy-duty diesel vehicle comprising an exhaust system (32) comprising a composite oxidation catalyst (12, 42) and a soot filter substrate (44, 50) disposed downstream from the composite oxidation catalyst comprising: a substrate (5), preferably a honeycomb flow-through substrate monolith, having a total length L and a longitudinal axis and having a substrate surface extending axially between a first substrate end (I) and a second substrate end (O); two catalyst washcoat zones (1, 2) arranged axially in series on and along the substrate surface, wherein a first catalyst washcoat zone (1) having a length L.sub.1 and comprising a first catalyst washcoat layer (9), wherein L.sub.1<L, is defined at one end by the first substrate end (I) and at a second end by a first end (15) of a second catalyst washcoat zone (2) having a length L.sub.2 and comprising a second catalyst washcoat layer (11), wherein L.sub.2<L, wherein the second catalyst washcoat zone (2) is defined at a second end thereof by the second substrate end (O), and wherein the first substrate end (I) of the composite oxidation catalyst (12, 42) is oriented to an upstream side and wherein the first catalyst washcoat zone (1) comprises a first refractory metal oxide support material and two or more platinum group metal components supported thereon comprising both platinum and palladium at a weight ratio of platinum to palladium of <1; and the second catalyst washcoat zone (2) comprises a second refractory metal oxide support material and one or more platinum group metal components supported thereon; and a washcoat overlayer (G) extending axially from the first substrate end (I) comprising a particulate metal oxide having a loading of >48.8 g/l (>0.8 g/in.sup.3), wherein a total platinum group metal loading in the first catalyst washcoat zone (1) defined in grams of platinum group metal per litre of substrate volume (g/l) is greater than a total platinum group metal loading in the second catalyst washcoat zone (2) and wherein the first catalyst washcoat zone (1) comprises one or more first alkaline earth metal components, preferably barium, supported on the first refractory metal oxide support material.

Provided are multi-zone catalyst articles, methods of manufacturing multi-zone catalyst articles, and methods for controlling emissions in diesel engine exhaust streams with multi-zone catalyst articles, where the emission treatment system of various embodiments effectively treats diesel engine exhaust with a single multi-zone catalyst article.

A catalyst article for treating exhaust gas from a gasoline engine comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the inlet end and extending for less than the axial length L, wherein the first catalytic region comprises a first PGM component and a first inorganic oxide; a second catalytic region beginning at the outlet end, wherein the second catalytic region comprises a second PGM component, a second oxygen storage capacity (OSC) material, and a second inorganic oxide; wherein the first catalytic region is substantially free of ceria; and wherein the first PGM component is palladium (Pd), platinum (Pt) or a combination thereof.

Catalyst articles having an ammonia slip catalyst (ASC) comprising a blend of platinum on a support with low ammonia storage and a first SCR catalyst, and a second catalyst, such as a diesel oxidation catalyst, a diesel exotherm catalyst (DEC), a NOx absorber, a selective catalytic reduction/passive NOx adsorber (SCR/PNA), a cold-start catalyst (CSC) or a three-way catalyst (TWC) are disclosed. The catalyst articles can also contain one or two additional SCR catalysts. The catalysts can be present in one of various configurations. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases and in reducing the amount of ammonia slip. Methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced, are also described.

Catalyst articles having a first zone containing a first SCR catalyst and a second zone containing an ammonia slip catalyst (ASC), where the ammonia slip catalyst contains a second SCR catalyst and an oxidation catalyst, and the ASC has DOC functionality, where the first zone is located on the inlet side of the substrate and the second zone is located in the outlet side of the substrate are disclosed. The catalytic articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases, in reducing the amount of ammonia slip and in oxidizing organic residues. Exhaust systems containing the catalyst articles and methods of using the catalytic articles in an SCR process, where the amount of ammonia slip is reduced and hydrocarbon are oxidized by the ASC catalyst, are also described.

Provided are automotive catalyst composites having a catalytic material on a carrier, wherein the catalytic material comprises at least two layers. The first layer is deposited directly on the carrier and comprises a first palladium component supported on a first refractory metal oxide component, a first oxygen storage component, or a combination thereof. The second layer is deposited on top of the first layer and comprises a rhodium component supported on a second refractory metal oxide component and a second palladium component supported on a second oxygen storage component, a third refractory metal oxide component or a combination thereof. Generally these catalyst composites are used as three-way conversion (TWC) catalysts. Methods of making and using the same are also provided.

A composite oxidation catalyst for use in an exhaust system for treating an exhaust gas produced by a vehicular compression ignition internal combustion engine is disclosed. The composite oxidation catalyst comprises a honeycomb flow-through substrate monolith and two catalyst washcoat zones arranged axially in series on and along the substrate surface.

The present invention is directed to a wall-flow filter which is used in particular in exhaust gas systems of vehicles driven by gasoline engines. The filter has three-way activity and filters fine particles, which result from the combustion of gasoline, from the exhaust gas stream. The invention also relates to a method for producing a corresponding filter and to the preferred use thereof.