A process for synthesizing an azo compound by oxidation of a hydrogen compound in the presence of a catalyst and a compound of formula (I) is described in which R.sub.1, R.sub.2 and R.sub.3

(R.sub.1)(R.sub.2)C(PO.sub.3(R.sub.3).sub.2).sub.2(I)

are as defined. The use of a compound of formula (I) as complexing agent for a catalyst is also described.

The invention relates to a catalyst comprising a support, at least one noble metal M, tin, phosphorus and yttrium, the content of phosphorus element being less than or equal to 1% by weight, and the content of yttrium being less than or equal to 1% by weight relative to the mass of the catalyst. The invention also relates to the process for preparing the catalyst and to the use thereof in reforming.

A method for producing calcium phosphate by the present invention is characterized by comprising the steps of: (a) preparing a 0.5-1.5 M aqueous calcium salt solution, a 0.3-0.8 M aqueous phosphate solution, and a 0.1-0.5 M aqueous carbonate solution; (b) mixing the aqueous phosphate solution and the aqueous carbonate solution in step (a) to prepare a mixture solution; (c) adding an aqueous alkaline solution to the aqueous calcium salt solution in step (a); (d) adding an aqueous alkaline solution to the mixture solution in step (b); (e) mixing and reacting the aqueous calcium salt solution with the aqueous alkaline solution added thereto in step (c) and the mixture solution with the aqueous alkaline solution added thereto in step (d) to prepare a precipitate; and (f) filtering, washing, and drying the precipitate in step (e) to obtain calcium phosphate, wherein the primary particle size of the calcium phosphate is 100 nm or smaller and the specific surface area thereof is 40-150 m2/g.

A water treatment system with a photocatalytic nanocomposite sheet, an adsorbent layer, and a fibrous filter, wherein the photocatalytic nanocomposite sheet comprises polymethylmethacrylate and silver phosphate, the adsorbent layer comprises plasma activated carbon nanotubes, and the fibrous filter is a composite of polymethylmethacrylate, polyvinylidene fluoride, and polyvinylpyrrolidone polymer fibers, with carbon nanotubes that are dispersed within the polymer fibers and silver nanoparticles that are deposited on the polymer fibers. Various embodiments of the water treatment system and methods of fabricating the photocatalytic nanocomposite sheet, the adsorbent layer, and the fibrous filter are also provided.

A water treatment system with a photocatalytic nanocomposite sheet, an adsorbent layer, and a fibrous filter, wherein the photocatalytic nanocomposite sheet comprises polymethylmethacrylate and silver phosphate, the adsorbent layer comprises plasma activated carbon nanotubes, and the fibrous filter is a composite of polymethylmethacrylate, polyvinylidene fluoride, and polyvinylpyrrolidone polymer fibers, with carbon nanotubes that are dispersed within the polymer fibers and silver nanoparticles that are deposited on the polymer fibers. Various embodiments of the water treatment system and methods of fabricating the photocatalytic nanocomposite sheet, the adsorbent layer, and the fibrous filter are also provided.

The present disclosure relates to a composition that includes a first oxide having a phosphate, a ratio of Brnsted acid sites to Lewis acid sites between 0.05 and 1.00, and a total acidity between 50 mol/g and 300 mol/g, where the phosphate is at least one of a functional group covalently bonded to the first oxide and/or an anion ionically bonded to the first oxide.

The present invention relates to a composition for use in a catalyst system in emission control systems comprising a transition alumina based material and rare earth phosphates and to a method for making same.

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.

A composition or material, in particular a catalytically active composition or material, a process for producing the composition or material, a composition or material obtained or obtainable by the process, and uses of the composition or material. The composition or material includes a permanently polarized hydroxyapatite and a brushite and/or a brushite-like material.

Disclosed herein are processes of making furan-based polyamides using solvent-free melt condensation of a diamine and an ester derivative of 2,5-furandicarboxylic acid with a C.sub.2 to C.sub.12 aliphatic diol or a polyol. The processes comprise a) forming a reaction mixture by mixing one or more diamines, a diester comprising an ester derivative of 2,5-furandicarboxylic acid with a C.sub.2 to C.sub.12 aliphatic diol or a polyol, and a catalyst, such that the diamine is present in an excess amount of at least 1 mol % with respect to the diester amount; and b) melt polycondensing the reaction mixture in the absence of a solvent at a temperature in the range of 60 C. to a maximum temperature of 250 C. under an inert atmosphere, while removing alkyl alcohol to form a furan-based polyamide, wherein the one or more diamines comprises an aliphatic diamine, an aromatic diamine, or an alkylaromatic diamine.