A core-shell composite material may include a core consisting of Nb-doped TiO.sub.2 of formula TiNbO.sub.x; and a shell consisting of a homogeneous layer of Pt or Pt alloy of 1 to 50 ML in thickness. The core-shell composite material may in particular find application in fuel cells.

Provided is a novel production system that does not involve, or can minimize, the transport of liquid ammonia in the production of an organic compound or the production of a microorganism by microbial fermentation. A production system for an organic compound or a microorganism includes: an ammonia synthesis apparatus in which an ammonia-containing gas is synthesized by reaction of a source gas containing hydrogen and nitrogen in the presence of a supported ruthenium catalyst; and a culture apparatus that cultures a microorganism having organic compound productivity using ammonia originating from the ammonia-containing gas obtained by using the ammonia synthesis apparatus.

Disclosed herein are base metal catalyst devices for removing ozone, volatile organic compounds, and other pollutants from an air flow stream. A catalyst device includes a housing, a solid substrate disposed within the housing, and a catalyst layer disposed on the substrate. The catalyst layer includes a first base metal catalyst at a first mass percent, a second base metal catalyst at a second mass percent, and a support material impregnated with at least one of the first base metal catalyst or the second base metal catalyst. The preferred catalyst composition is a combination of manganese oxide and copper oxide.

A catalyst for decomposing perfluorinated compounds includes an alumina carrier, at least one metal carried on the alumina carrier and selected from the group consisting of Zn, Ni, W, Zr, Ti, Ga, Nb, Co, Mo, V, Cr, Mn, Fe, and Cu, S carried on the alumina carrier, and rare-earth metals carried on the alumina carrier.

According to various aspects and embodiments, multilayer particles having an irregular surface architecture and methods of making the same are disclosed.

Disclosed are metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles having high dispersibility. The metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles having high dispersibility can be obtained by containing metal nitride photoctalyst particles and/or metal oxynitride photocatalyst particles, which are capable of splitting water under visible light irradiation, and a phosphoric acid polymer that is adsorbed on the surface of the particles. Further, because these particles have high photocatalytic activity under visible light irradiation, splitting water by using these particles can generate hydrogen and/or oxygen with high efficiency.

A selective hydrogenation catalyst contains an active phase having a group VIB metal and a group VIII metal, and a porous support containing alumina. The group VIB metal content is between 1 and 18% by weight relative to total weight of the catalyst, and the group VIII metal content of the active phase, measured in oxide form, is between 1 and 20% by weight relative to total weight of the catalyst. The molar ratio between the group VIII metal and the group VIB metal is between 1.0 and 3.0 mol/mol. The group VIII metal is homogeneously distributed in the porous support with a distribution coefficient R of between 0.8 and 1.2, measured using a Castaing microprobe, and the group VIB metal is distributed at the periphery of the porous support with a distribution coefficient R of less than 0.8.

The invention discloses a core-shell structured catalyst comprising a core covered with a shell. The core is made of hematite, tourmaline, germanium, maifanite or kaolin. The invention also provides a method for preparing the catalyst including mixing raw materials of the core with water to form seed-balls with a particle size of 2-4 mm; mixing the seed-balls with raw materials of the shell and water, such that the seed-balls are covered with the raw materials of the shell to form pellets with a particle size of 3-5 mm; processing the pellets at 60-90° C. and then calcining to active the pellets at 450-550° C. to obtain a core-shell structured catalyst. The invention further discloses use of the core-shell structured catalyst in the ozone oxidation reaction. In the invention, a core-shell structured catalyst with good morphology and catalytic performance is prepared, and the production cost of the catalyst is reduced.

The oxide-containing particles (transition metal oxide-containing cerium dioxide particle) exert a catalyst performance, and include at least an iron oxide containing an iron component and a manganese oxide containing a manganese component on a surface of each of cerium dioxide particles, wherein the iron oxide and manganese oxide have smaller particle diameters than that of the cerium dioxide particles, and the content rate of the iron oxide and the manganese oxide is within the range of from 15.0% by mass to 35.0% by mass.

Provided is a method for producing at least one of an unsaturated aldehyde and an unsaturated carboxylic acid from an alkene by an oxidation reaction, in which a n-layered catalyst layer (n≥2) is provided in a gas flow direction in a reaction tube, two or more kinds of catalysts having different activities are used; and the catalysts are packed in such a manner that dT≤20° C. is satisfied, when a difference between a temperature PT.sub.n of an exothermic peak in a n-th layer as counted from a gas inlet and a minimum value mT.sub.n−1 of a temperature of a catalyst layer which appears between an exothermic peak in a (n-1)th layer and an exothermic peak in a n-th layer from the gas inlet is represented as dT (=PT.sub.n−mT.sub.n−1), and the change rate of dT is 2.5 or less at a reaction bath temperature within a range of ±6° C. of a reaction bath temperature at which the highest yield is obtained.