A catalyst containing, as an essential component, molybdenum; bismuth; and cobalt, in which, with respect to a peak intensity at 2θ=25.3°±0.2° in an X-ray diffraction pattern obtained by using CuKα rays as an X-ray source, a changing rate (Q1) per 1000 hours of reaction time represented by the following formulae (1) to (4) is 16 or less.

Q1={(U1/F1−1)×100}/T×1000  (1)

F1=(peak intensity of catalyst before oxidation reaction at 2θ=25.3°±)0.2°/(peak intensity of catalyst before oxidation reaction at 2θ=26.5°±0.2°)×100  (2)

U1=(peak intensity of catalyst after oxidation reaction at 2θ=25.3°±0.2°)/(peak intensity of catalyst after oxidation reaction at 2θ=26.5°±0.2°)×100  (3)

T=time (hr) during which oxidation reaction is carried out  (4)

A catalyst may suppress pressure loss and coaking and produce a target substance in high yield when a gas-phase catalytic oxidation reaction of a material substance is conducted using the catalyst to produce the target substance. A ring-shaped catalyst may have a straight body part and a hollow body part, which is used when a gas-phase catalytic oxidation reaction of a material substance is conducted to produce a target substance, wherein a length of the straight body part is shorter than a length of the hollow body part and at least at one end part, a region from an end part of the straight body part to an end part of the hollow body part is concavely curved.

Provided are catalyst particles for treating vehicle exhaust gas, containing semiconductor nanoparticles supported by noble metals.

A method of purifying air polluted by smoke and fumes, such as from wildfires and other hazard, may deploy a series of fluid filled vessels that act as filters to trap and/or neutralize components that would foul an aqueous suspension of gold nanoparticles that is effective in converting toxic carbon monoxide to carbon dioxide. Non-toxic fluids may be used. As the gold nanoparticles are effective in a basic solution, the solution may contain a visible pH indicator or an apparatus that deploys the method may continuously monitor the pH thereof.

A catalyst system includes a porous polymeric base, a nanoscale metal catalyst layer disposed on the porous polymeric base, and a nanoscale electrolyte layer disposed on the metal catalyst layer. The catalyst system is used in methods to perform three-phase catalytic reactions.

A catalyst structure for synthesis gas production of a synthesis gas that contains carbon monoxide and hydrogen, the catalyst structure being provided with a carrier that has a porous structure, while being configured from a zeolite type compound; first catalyst particles that contain one or more iron group elements which are selected from the group consisting of nickel (Ni), iron (Fe) and cobalt (Co); and second catalyst particles that contain one or more platinum group elements which are selected from the group consisting of platinum (Pt), palladium (Pd), rhodium (Rh) and ruthenium (Ru). The catalyst structure for synthesis gas production has passages in communication with each other within the carrier. The first catalyst particles are present at least in the passages of the carrier; and the second catalyst particles are present at least either inside the carrier or on the outer surface of the carrier.

An object of the present invention is to provide a composition for forming an undercoat layer capable of forming an undercoat layer that does not easily peel off from the substrate, an undercoat layer formed by the composition, as well as an exhaust gas purification catalyst and an exhaust gas purification apparatus each including the undercoat layer, and, to achieve the object, the present invention provides a composition for forming an undercoat layer, the composition containing tin oxide microparticles and tin oxide nanoparticles, wherein a content of the tin oxide nanoparticles is 8% by mass or more and 30% by mass or less, with respect to a total content of the tin oxide microparticles and the tin oxide nanoparticles, an undercoat layer formed by the composition, as well as an exhaust gas purification catalyst and an exhaust gas purification apparatus each including the undercoat layer.

The present disclosure provides an improved shaped catalyst containing catalytic material comprised of mixed oxides of vanadium and phosphorus and using such shaped catalysts for the production of maleic anhydride.

Disclosed herein is a method of treating an aqueous solution containing impurities including a perfluoroalkyl substance and/or a polyfluoroalkyl substance, comprising introducing the aqueous solution into a batch or semi-batch photocatalytic reactor with a microparticulate catalyst configured to reduce chain length of the perfluoroalkyl substance and/or polyfluoroalkyl substance, forming a treated aqueous stream, the reactor including a catalyst flow controller configured to automatically increase the catalyst concentration in the reactor while agitating the catalyst-containing solution during reaction, and removing catalyst particles from the treated aqueous stream to form a purified aqueous stream. In some cases, the feed to the reactor is atomized. Corresponding systems also are disclosed.

The present invention relates to a process for preparing a cobalt-containing Fischer-Tropsch synthesis catalyst with good physical properties and high cobalt loading. In one aspect, the present invention provides a process for preparing a supported cobalt-containing Fischer-Tropsch synthesis catalyst, said process comprising the following steps of: (a) impregnating a support powder or granulate with a cobalt-containing compound; (b) calcining the impregnated support powder or granulate and extruding to form an extrudate; or extruding the impregnated support powder or granulate to form an extrudate and calcining the extrudate; and (c) impregnating the calcined product with a cobalt-containing compound; or forming a powder or granulate of the calcined product, impregnating with a cobalt-containing compound and extruding to form an extrudate.