A process for producing an oligomerization catalyst includes hydrothermal treatment. An oligomerization catalyst produced by the process is useful for the oligomerization of C.sub.2 to C.sub.12 olefins.

The present invention relates to a composite oxide comprising ceria, praseodymia and alumina, wherein the cerium:praseodymium molar ratio of the composite oxide is 84:16 or less, as well as to a method of preparing the composite oxide and to its use, in particular in a method of treating an exhaust gas stream.

Proposed inventions are a recipe of denitrification-oxidation complex catalyst containing an SCR catalyst and an oxidation catalyst to simultaneously remove nitrogen oxides, carbon monoxide, hydrocarbons, and ammonia, a manufacturing method thereof, an exhaust gas treatment method using the denitrification-oxidation complex catalyst, and an SCR denitrification system including the denitrification-oxidation complex catalyst. The denitrification-oxidation complex catalyst simultaneously removes nitrogen oxides, carbon monoxide, hydrocarbons, and ammonia and exhibits an increased catalytic effect compared to the cases where the denitrification catalyst used alone and the denitrification and the oxidation catalyst ratios are and not properly balanced. When the denitrification-oxidation complex catalyst is applied to an SCR denitrification system, the structure is simplified, space is saved, cost is reduced, and catalyst maintenance is easy.

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.

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.

An electrocatalyst material comprising cuprous oxide and antimony, the process for the production thereof and its use in the electrochemical reduction of CO.sub.2 to CO with high selectivity and efficiency are described.

This application consists of a method for the synthesis of a type of FER/MOR composite molecular sieve. That method consisting of mixing FER seed crystals, MOR seed crystals, a silicon source, water and an acid or alkali, thus yielding a reaction mixture; by adjusting the proportions of the seed crystals added, the silicon-aluminium proportion, acidity/alkalinity and other reaction conditions, it is possible to obtain a dual phase composite molecular sieve within which the proportions of the crystal phases may be adjusted. In the synthesis process to which the method of this application relates, there is no need to add any organic template, thus reducing the cost of the reaction, in addition to reducing likely environmental pollution, thus having major potential applications.

A catalyst composition comprising—a support comprising TiO.sub.2,—a composite oxide containing vanadium and antimony, which has a rutile-type structure different from VSbO.sub.4 and V.sub.0.92Sb.sub.0.92O.sub.4 as determined by X-ray diffraction (XRD) analysis with CuKα radiation, and—optionally, one or more selected from the group consisting of oxides of silicon, oxides of vanadium and oxides of antimony, for selective catalytic reduction of nitrogen oxides; to a process for preparing the catalyst composition, to the catalyst composition obtained/obtainable by the process and to use of the same for selective catalytic reduction of nitrogen oxides.

A catalyst composition comprising—a support comprising TiO.sub.2,—a composite oxide containing vanadium and antimony, which has a rutile-type structure different from VSbO.sub.4 and V.sub.0.92Sb.sub.0.92O.sub.4 as determined by X-ray diffraction (XRD) analysis with CuKα radiation, and—optionally, one or more selected from the group consisting of oxides of silicon, oxides of vanadium and oxides of antimony, for selective catalytic reduction of nitrogen oxides; to a process for preparing the catalyst composition, to the catalyst composition obtained/obtainable by the process and to use of the same for selective catalytic reduction of nitrogen oxides.

The present invention pertains to a catalyst for use in the selective catalytic reduction (SCR) of nitrogen oxides comprising a monolithic substrate and a coating A, which comprises an oxidic metal carrier comprising an oxide of titanium and a catalytic metal oxide which comprises an oxide of vanadium wherein the mass ratio vanadium/titanium is 0.07 to 0.26.