A catalyst system comprising a first catalytic composition comprising a homogeneous solid mixture containing at least one catalytic metal and at least one metal inorganic support. The pores of the solid mixture have an average diameter in a range of about 1 nanometer to about 15 nanometers. The catalytic metal comprises nanocrystals.

A promoted VPO catalyst for the oxidation of n-butane to maleic anhydride wherein the catalyst comprises the mixed oxides of vanadium and phosphorus, niobium and at least one of antimony and bismuth, wherein the catalyst may be produced in a process comprising impregnating a VPO catalyst with a metal source compound of niobium and a metal source compound of at least one of antimony and bismuth, to form a metal impregnated VPO catalyst, and then drying the metal impregnated VPO catalyst to form the promoted VPO catalyst.

A supported catalyst particles include oxide carrier particles and noble metal particles supported on the oxide carrier particles, wherein the mass of the noble metal particles is less than or equal to 5 mass % based on the mass of the oxide carrier particles, and the average particle size of the noble metal particles measured by transmission electron microscopy is 1.0-2.0 nm, with the standard deviation less than or equal to 0.8 nm.

The present invention relates to a water treatment agent, a preparation method therefor, a water treatment apparatus using the same, and an in-situ groundwater treatment apparatus and, more specifically, to: a water treatment agent comprising a carbon nanotube support, and -manganese dioxide nanoparticles adsorbed on the carbon nanotube support and having a particle size of 1,000 nm or less; a preparation method therefor; a water treatment apparatus using the same; and an in-situ groundwater treatment apparatus.

Disclosed are a complex oxide catalyst for dehydrogenation, a method of preparing the same, and use thereof, wherein the catalyst includes a first transition metal selected from the group consisting of gallium, vanadium, chromium, manganese, molybdenum, and zinc, a hydrogen-activating metal including at least one selected from the group consisting of Groups 8, 9, 10, and 11 elements in a periodic table, and alumina, the amount of the first transition metal being 0.1 wt % to 20 wt %, the amount of the hydrogen-activating metal being 0.01 wt % to 2 wt %, based on the amount of the alumina, the first transition metal being loaded on the alumina, and the hydrogen-activating metal being surrounded by the alumina.

A metal compound catalyst is formed by vaporizing a quantity of catalyst material and a quantity of carrier thereby forming a vapor cloud, exposing the vapor cloud to a co-reactant and quenching the vapor cloud. The nanoparticles are impregnated onto supports. The supports are able to be used in existing heterogeneous catalysis systems. A system for forming metal compound catalysts comprises means for vaporizing a quantity of catalyst material and a quantity of carrier, quenching the resulting vapor cloud, forming precipitate nanoparticles comprising a portion of catalyst material and a portion of carrier, and subjecting the nanoparticles to a co-reactant. The system further comprises means for impregnating the of supports with the nanoparticles.

An oxide catalyst is formed by vaporizing a quantity of at least one precursor material or catalyst material thereby forming a vapor cloud. The vapor cloud is quenched forming precipitate nanoparticles. The nanoparticles are impregnated onto supports. The supports are able to be used in existing heterogeneous catalysis systems. A system for forming oxide catalysts comprises means for vaporizing a quantity of at least one precursor material or at least one catalyst material, quenching the resulting vapor cloud and forming precipitate nanoparticles. The system further comprises means for supports with the nanoparticles.

A metal catalyst is formed by vaporizing a quantity of metal and a quantity of carrier forming a vapor cloud. The vapor cloud is quenched forming precipitate nanoparticles comprising a portion of metal and a portion of carrier. The nanoparticles are impregnated onto supports. The supports are able to be used in existing heterogeneous catalysis systems. A system for forming metal catalysts comprises means for vaporizing a quantity of metals and a quantity of carrier, quenching the resulting vapor cloud and forming precipitate nanoparticles comprising a portion of metals and a portion of carrier. The system further comprises means for impregnating supports with the nanoparticles.

Disclosed are catalysts comprised of platinum and gold. The catalysts are generally useful for the selective oxidation of compositions comprised of a primary alcohol group and at least one secondary alcohol group wherein at least the primary alcohol group is converted to a carboxyl group. More particularly, the catalysts are supported catalysts including particles comprising gold and particles comprising platinum, wherein the molar ratio of platinum to gold is in the range of about 100:1 to about 1:4, the platinum is essentially present as Pt(0) and the platinum-containing particles are of a size in the range of about 2 to about 50 nm. Also disclosed are methods for the oxidative chemocatalytic conversion of carbohydrates to carboxylic acids or derivatives thereof. Additionally, methods are disclosed for the selective oxidation of glucose to glucaric acid or derivatives thereof using catalysts comprising platinum and gold. Further, methods are disclosed for the production of such catalysts.

Niobia- and tantala-doped ceria catalysts, their use in selective catalytic reduction (SCR) processes, and a compact after-treatment system for exhaust gases are disclosed. In some aspects, the catalyst comprises at least 91 wt. % of ceria and 0.1 to 9 wt. % of niobia or tantala doped on the ceria. While conventional SCR catalysts can deactivate at higher temperatures, the doped cerias, particularly ones having as little as 1 or 2 wt. % of Nb.sub.2O.sub.5 or Ta.sub.2O.sub.5, are activated toward NOx conversion by calcination. The doped cerias are also valuable for SCRF catalyzed filter applications, including an after-treatment system that comprises a diesel particulate filter having inlets and outlets, and a dual-function catalyst coated on the inlets, outlets, or both. Compared with conventional SCR catalysts, the niobia or tantala-doped cerias enable a higher level of NO.sub.2 to be present.