A method of synthesizing an Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite, the method comprising: loading tungsten oxide (WO.sub.3) powder in a fluidized bed reactor followed by H.sub.2 treatment to produce reduced tungsten oxide (WO.sub.3) nanoparticles or WO.sub.3-x nanoparticles; producing reduced titanium dioxide (TiO.sub.2) nanoparticles or TiO.sub.2-y (containing defect states) nanoparticles in-situ; coupling the TiO.sub.2-y nanoparticles with the WO.sub.3-x nanoparticles to provide a titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x); and simultaneous substitutional doping of TiO.sub.2-y and WO.sub.3-x in the titanium dioxide/tungsten oxide nanocomposite (TiO.sub.2-y/WO.sub.3-x) with gold ions (Au) to obtain the Au(TiO.sub.2-y/WO.sub.3-x) semiconductor composite; wherein x has a value between 0.33 and 0.37. The thus produced composite can be used as a photocatalyst.

An object of the present invention is to provide an exhaust gas purifying catalyst composition and an exhaust gas purifying catalyst, each of which has improved exhaust gas purification performance, and the present invention provides an exhaust gas purifying catalyst composition containing a Ce-based oxide particle, a CeZr-based composite oxide particle, an Al-based oxide particle, and a noble metal element, wherein an amount of Ce in terms of CeO.sub.2 in the Ce-based oxide particle is 90% by mass or more based on a mass of the Ce-based oxide particle, wherein an amount of Ce in terms of CeO.sub.2 in the CeZr-based composite oxide particle is 5% by mass or more and 90% by mass or less based on a mass of the CeZr-based composite oxide particle, wherein the Ce-based oxide particle has an average particle size of 0.10 ?m or more and 15 ?m or less, and wherein an amount of the Ce-based oxide particle in the exhaust gas purifying catalyst composition is 2.0% by mass or more and 30% by mass or less based on a mass of the exhaust gas purifying catalyst composition.

The purpose of the present invention is to provide a catalyst that enables a hydrogenation reaction of cyclopentadiene to cyclopentene in a gas phase that exhibits both a high conversion rate and high selectivity, and a method for producing the cyclopentene in a gas phase that exhibits both a high conversion rate and high selectivity. A catalyst according to the disclosure and a method for producing cyclopentadienecyclopentene according to the disclosure are a catalyst and a method for producing cyclopentene using the catalyst that is used in a hydrogenation reaction of cyclopentadiene in a gas phase to form the cyclopentene, the catalyst including palladium (Pd) and a titanium dioxide (TiO.sub.2) support, wherein the titanium dioxide (TiO.sub.2) support contains anatase-type titanium dioxide (TiO.sub.2).

The present invention relates to a method for preparing a catalyst which can produce carbon nanotubes having a higher bulk density by supporting a catalyst component under pressurized conditions, and to a method for producing carbon nanotubes using the catalyst so produced.

A method and catalyst for producing an alcohol, which method includes supplying water and a C2-C5 olefin to a reactor and performing hydration in a gas phase using a solid acid catalyst. The solid acid catalyst is one in which a heteropolyacid or a salt thereof is supported on a silica carrier. The silica carrier is obtained by kneading a fumed silica obtained by a combustion method, a silica gel obtained by a gel method, and a colloidal silica obtained by a sol-gel method or a water glass method; molding the resulting kneaded product; and calcining the resulting molded body.

A method for chemically reducing carbon dioxide (CO.sub.2) with a red mud catalyst composition is provided includes introducing a gaseous mixture of CO.sub.2 and H.sub.2 into a reactor containing particles of the red mud catalyst composition. The method further includes reacting at least a portion of the CO.sub.2 and H.sub.2 in the gaseous mixture in the presence of the red mud catalyst composition at a temperature of 200 to 800? C., and under a pressure ranging from 5 to 100 bar to form a gaseous product including a chemical reduction product of the CO.sub.2. A volume ratio of the CO.sub.2 to the H.sub.2 in the gaseous mixture is in a range of 1:10 to 10:1.

There are provided, for example, a reducing agent that can be used in a chemical looping method, a method of producing a gas using such a reducing agent and a method of increasing conversion efficiency, through which the efficiency of converting carbon dioxide into carbon monoxide is high. The reducing agent of the present invention is a reducing agent that produces valuables containing carbon by reducing carbon dioxide, including a granular support having a plurality of pores and an angle of repose of 45? or more and an oxygen carrier which is supported on the support and has oxygen ion conductivity. In addition, in the reducing agent of the present invention, the support preferably has an average pore size of 0.1 nm or more.

An object of the present invention is to provide an exhaust gas purification catalyst composition and an exhaust gas purification catalyst, each of which utilizes a phosphorus capturing material that enables solving a problem of MAO, and in order to achieve the object, a complex oxide containing Mg, Ba, and Al, wherein the complex oxide has a spinel-type crystal structure, and wherein a molar ratio of a Mg content to an Al content in the complex oxide is 0.010 or more and 0.25 or less is used as a phosphorus capturing material.

Fluorided silica-coated alumina activator-supports have a bulk density from 0.15 to 0.37 g/mL, a total pore volume from 0.85 to 2 mL/g, a BET surface area from 200 to 500 m.sup.2/g, an average pore diameter from 10 to 25 nm, and from 80 to 99% of pore volume in pores with diameters of greater than 6 nm. Methods of making the fluorided silica-coated alumina activator-supports and using the fluorided silica-coated aluminas in catalyst compositions and olefin polymerization processes also are described. Representative ethylene-based polymers produced using the compositions and processes have a melt index of 0.1 to 10 g/10 min and a density of 0.91 to 0.96 g/cm.sup.3, and contain from 70 to 270 ppm solid oxide and from 2 to 18 ppm fluorine.

An object of the present invention is to provide an exhaust gas purifying catalyst composition and an exhaust gas purifying catalyst, each of which has improved exhaust gas purification performance, and the present invention provides an exhaust gas purifying catalyst composition containing a Ce-based oxide particle, a CeZr-based composite oxide particle, and a noble metal element, wherein the Ce-based oxide particle contains at least one type of additional element selected from Al, Mg, La, Pr, Y, and Nd, and wherein an amount of the at least one type of additional element in terms of oxide in the Ce-based oxide particle is 0.1% by mass or more and 20% by mass or less based on a mass of the Ce-based oxide particle.