A particulate filter disclosed herein includes a wall-flow structure substrate 10 and a wash coat layer 20 held inside a partition 16 of the substrate 10. The wash coat layer 20 includes an inlet layer 22 formed to have predetermined length L.sub.A and thickness T.sub.A from near an end thereof on an exhaust gas inflow side X1, and an outlet layer 24 formed to have predetermined length L.sub.B and thickness T.sub.B from near an end thereof on an exhaust gas outflow side X2. The inlet layer 22 and the outlet layer 24 partially overlap each other. In the particulate filter disclosed herein, the inlet layer 22 contains a precious metal catalyst, while the outlet layer 24 contains substantially no precious metal catalyst. The length L.sub.A of the inlet layer is 50% or more and 75% or less of a total length L of the partition 16. Thus, the particulate filter is capable of achieving both PM collection performance and pressure-drop reduction performance at high levels.

A particulate filter disclosed herein includes a wall-flow structure substrate 10 and a wash coat layer 20 held inside a partition 16 of the substrate 10. The wash coat layer 20 includes an inlet layer 22 formed to have predetermined length L.sub.A and thickness T.sub.A from near an end thereof on an exhaust gas inflow side X1, and an outlet layer 24 formed to have predetermined length L.sub.B and thickness T.sub.B from near an end thereof on an exhaust gas outflow side X2. The inlet layer 22 and the outlet layer 24 partially overlap each other. In the particulate filter disclosed herein, the inlet layer 22 contains a precious metal catalyst, while the outlet layer 24 contains substantially no precious metal catalyst. The length L.sub.A of the inlet layer is 50% or more and 75% or less of a total length L of the partition 16. Thus, the particulate filter is capable of achieving both PM collection performance and pressure-drop reduction performance at high levels.

To provide a uniform-type platinum-loaded alumina catalyst demonstrating excellent performance in terms of catalyst life, a uniform-type platinum-loaded alumina catalyst includes: an alumina carrier; sulfur or a sulfur compound dispersed over an entire cross section of the alumina carrier; platinum dispersed and loaded over the entire cross section of the alumina carrier; one or more alkali metals selected from the group consisting of sodium, potassium, and calcium. Preferably, the content of platinum is 0.05 to 5.0 wt % calculated as elemental platinum. The content of the sulfur or the sulfur compound preferably is 0.15 to 5.0 wt % calculated as elemental sulfur. The content of the alkali metal preferably is 0.1 to 5.0 wt % calculated as elemental alkali metal.

To provide a uniform-type platinum-loaded alumina catalyst demonstrating excellent performance in terms of catalyst life, a uniform-type platinum-loaded alumina catalyst includes: an alumina carrier; sulfur or a sulfur compound dispersed over an entire cross section of the alumina carrier; platinum dispersed and loaded over the entire cross section of the alumina carrier; one or more alkali metals selected from the group consisting of sodium, potassium, and calcium. Preferably, the content of platinum is 0.05 to 5.0 wt % calculated as elemental platinum. The content of the sulfur or the sulfur compound preferably is 0.15 to 5.0 wt % calculated as elemental sulfur. The content of the alkali metal preferably is 0.1 to 5.0 wt % calculated as elemental alkali metal.

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 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 catalytic composite comprises a first component selected from Group VIII noble metal components and mixtures thereof, a second component selected from one or more of alkali and alkaline earth metal components, and a third component selected from one or more of tin, germanium, lead, indium, gallium, and thallium, all supported on an alumina support comprising delta alumina having an X-ray diffraction pattern comprising at least three 2θ diffraction angle peaks between 32.0° and 70.0°. The at least three 2θ diffraction angle peaks comprise a first 2θ diffraction angle peak of 32.7°±0.4°, a second 2θ diffraction angle peak of 50.8°±0.4°, and a third 2θ diffraction angle peak of 66.7°±0.8°, wherein the second 2θ diffraction angle peak has an intensity of less than about 0.06 times the intensity of the third 2θ diffraction angle peak.

A catalytic composite comprises a first component selected from Group VIII noble metal components and mixtures thereof, a second component selected from one or more of alkali and alkaline earth metal components, and a third component selected from one or more of tin, germanium, lead, indium, gallium, and thallium, all supported on an alumina support comprising delta alumina having an X-ray diffraction pattern comprising at least three 2θ diffraction angle peaks between 32.0° and 70.0°. The at least three 2θ diffraction angle peaks comprise a first 2θ diffraction angle peak of 32.7°±0.4°, a second 2θ diffraction angle peak of 50.8°±0.4°, and a third 2θ diffraction angle peak of 66.7°±0.8°, wherein the second 2θ diffraction angle peak has an intensity of less than about 0.06 times the intensity of the third 2θ diffraction angle peak.

A method for producing a shell catalyst which comprises, in the outer shell, one or more of the following metals: Pd, Pt, Ag and Au. Also the use of the shell catalyst produced using the method according to the invention for the production of vinyl acetate monomer, in the hydrogenation of hydrocarbons, in particular the selective hydrogenation of polyunsaturated hydrocarbon compounds, or in the oxidation of alcohols to ketones/aldehydes/carboxylic acids.

A method for producing a shell catalyst which comprises, in the outer shell, one or more of the following metals: Pd, Pt, Ag and Au. Also the use of the shell catalyst produced using the method according to the invention for the production of vinyl acetate monomer, in the hydrogenation of hydrocarbons, in particular the selective hydrogenation of polyunsaturated hydrocarbon compounds, or in the oxidation of alcohols to ketones/aldehydes/carboxylic acids.