A heterogeneous catalyst comprising a support and a noble metal, wherein said support comprises silicon, and wherein said catalyst comprises from 0.1 to 40 mol % titanium and from 0.1 to 10 mol % of at least one noble metal.

Catalyst containing an active phase which contains a group VIB element, at least one group VIII element and phosphorus, and a support containing alumina, the catalyst being characterized in that at least 80% by weight of the group VIB elements, of the group VIII elements and of the phosphorus are distributed in the form of a crust at the periphery of said support, the thickness of said crust being between 100 and 1200 μm, the content of group VIB element being between 1% and 8% by weight relative to the total weight of the catalyst, the content of group VIII element being between 0.5% and 5% by weight relative to the total weight of the catalyst, and the content of phosphorus being between 0.2% and 3% by weight relative to the total weight of the catalyst, and the support having a specific surface area of between 100 m.sup.2/g and 250 m.sup.2/g.

Catalyst containing an active phase which contains a group VIB element, at least one group VIII element and phosphorus, and a support containing alumina, the catalyst being characterized in that at least 80% by weight of the group VIB elements, of the group VIII elements and of the phosphorus are distributed in the form of a crust at the periphery of said support, the thickness of said crust being between 100 and 1200 μm, the content of group VIB element being between 1% and 8% by weight relative to the total weight of the catalyst, the content of group VIII element being between 0.5% and 5% by weight relative to the total weight of the catalyst, and the content of phosphorus being between 0.2% and 3% by weight relative to the total weight of the catalyst, and the support having a specific surface area of between 100 m.sup.2/g and 250 m.sup.2/g.

Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

Catalysts for oxidative esterification can be used, for example, fro converting (meth)acrolein to methyl (meth)acrylate. The catalysts are especially notable for high mechanical and chemical stability even over very long time periods, including activity and/or selectivity relatively in continuous operation in media having even a small water content.

An object of the present invention is to provide ferrite particles for supporting a catalyst having a small apparent density, various properties are maintained in a controllable state and a specified volume is filled with a small weight, and a catalyst using the ferrite particles for supporting a catalyst. To achieve the object, ferrite particles for supporting a catalyst provided with an outer shell structure containing Ti oxide, a catalyst using the ferrite particles for supporting a catalyst are employed.

To provide electrode catalyst (core-shell catalyst) having an excellent catalyst activity which contributes to lower the cost of the PEFC. The electrode catalyst has catalyst particles supported an a support. The catalyst particle has a core part containing simple Pd and a shell part containing simple Pt. A percentage R.sub.C (atom %) of the carbon of the support and a percentage R.sub.Pd (atom %) of the simple Pd in an analytical region near a surface measured by X-ray photoelectron spectroscopy (XPS) satisfy the conditions of the following equation (1): 2.15≦[100×R.sub.Pd/(R.sub.Pd+R.sub.C)].

The present invention relates to a hybrid nanostructured photocatalyst, comprising a first nanoparticle comprising silver halide (AgX); a second nanoparticle, which is formed on an outer surface of the first nanoparticle and comprises Ag; and a polymer formed on any one outer surface of the first nanoparticle and the second nanoparticle, and a preparation method thereof. Specifically, the present invention provides a hybrid nanostructured photocatalyst having a high photocatalytic activity in a visible light region and a preparation method thereof.

The present invention relates to a hybrid nanostructured photocatalyst, comprising a first nanoparticle comprising silver halide (AgX); a second nanoparticle, which is formed on an outer surface of the first nanoparticle and comprises Ag; and a polymer formed on any one outer surface of the first nanoparticle and the second nanoparticle, and a preparation method thereof. Specifically, the present invention provides a hybrid nanostructured photocatalyst having a high photocatalytic activity in a visible light region and a preparation method thereof.

Disclosed are a spherelike supermacroporous mesoporous material, a polyolefin catalyst, and a preparation method therefor and an olefin polymerization process. The spherelike supermacroporous mesoporous material has a twodimensional hexagonal ordered pore channel structures. The mesoporous material has an average pore size of 10 nm to 15 nm, a specific surface area of 300 m.sup.2/g to 400 m.sup.2/g, and an average particle size of 1 .Math.m to 3 .Math.m, based on the total mass of the mesoporous material. The mass content of water in the mesoporous material is < 1 ppm. The mass content of oxygen in the mesoporous material is < 1 ppm. When a polyolefin catalyst prepared with the mesoporous material as a carrier is used for an olefin polymerization reaction, the a polyolefin product with a narrow molecular weight distribution and a good melt index can be obtained.