The invention relates to a mechanochemical process to produce exfoliated nanoparticles comprising the steps of providing a solid feedstock comprising a carbonaceous and/or mineral-based material; providing a flow of an oxidizing gas; introducing the solid feedstock and the flow of an oxidizing gas into a mechanical agitation unit, subjecting the material of the solid feedstock in the presence of the oxidizing gas to a mechanical agitation operation in the mechanical agitation unit at a pressure of at least 1 atm (15 psi).

The invention further relates to nanoparticles obtainable by the mechanochemical process and to the use of such nanoparticles.

The invention relates to O3/P2 mixed-phase sodium-containing doped layered oxide materials which comprise a mixture of a first phase with an O3-type structure and a second phase with a P2-type structure; wherein the O3:P2 mixed-phase sodium-containing doped layered oxide material has the general formula: Na.sub.aA.sub.bM.sup.1.sub.c M.sup.2 M.sup.3.sub.eM.sup.4.sub.f M.sup.5 O.sub.2±δ. The invention also provides a process for making such O3/P2 mixed-phase sodium-containing doped layered oxide materials, and use applications therefor.

A water purification apparatus and a water purification method capable of effectively using a layered double hydroxide and easily being applied are described. A water purification apparatus for removing a polluted substance from polluted water includes a solid-liquid separator that separates the polluted water and a solid material from each other, and a polluted substance remover that removes, by a layered double hydroxide, the polluted substance contained in the polluted water separated by the solid-liquid separator.

An object of the present invention is to provide ferrite particles having a high saturation magnetisation, and being excellent in the dispersibility in a resin, a solvent or a resin composition, a resin composition including the ferrite particles, and a resin film composed of the resin composition. The ferrite particles are a single crystalline body having an average particle size of 1 to 2000 nm, and Mn-based ferrite particles having a spherical shape, and have a saturation magnetisation of 45 to 95 Am.sup.2/kg. The resin composition includes the ferrite particles as a filler. The resin film is composed of the resin composition.

An object of the present invention is to provide ferrite particles having a high saturation magnetisation, and being excellent in the dispersibility in a resin, a solvent or a resin composition, a resin composition including the ferrite particles, and a resin film composed of the resin composition. The ferrite particles are a single crystalline body having an average particle size of 1 to 2000 nm, and Mn-based ferrite particles having a spherical shape, and have a saturation magnetisation of 45 to 95 Am.sup.2/kg. The resin composition includes the ferrite particles as a filler. The resin film is composed of the resin composition.

A method for preparing an aqueous dispersion of metal oxide particles is disclosed. The method comprises the step of performing phase transfer of a plurality of metal oxide particles capped with hydrophobic ligands on a surface there of by contacting the metal oxide particles with a combination of tertiary amine and water to form a biphasic mixture, and agitating said biphasic mixture to produce an aqueous dispersion of metal oxide particles capped with hydrophobic ligands and tertiary amine ligands on the surface thereof.

The powder of the magnetoplumbite-type hexagonal ferrite is an aggregate of particles of a compound represented by Formula (1), and, in a particle size distribution based on number measured by a laser diffraction scattering method, in a case where a mode value is defined as a mode diameter, a diameter at a cumulative percentage of 10% is defined as D10 and a diameter at a cumulative percentage of 90% is defined as D90, the mode diameter is equal to or greater than 5 μm and less than 10 μm and an expression of (D90−D10)/mode diameter≤3.0 is satisfied. In Formula (1), A represents at least one metal element selected from the group consisting of Sr, Ba, Ca, and Pb, and x satisfies 1.5≤x≤8.0.

AFe.sub.(12-x)Al.sub.xO.sub.19  Formula(1)

A powder mixture of a magnetoplumbite-type hexagonal ferrite is a mixture of powders of two or more kinds of compounds represented by Formula (1), the two or more kinds of compounds represented by Formula (1) are two or more kinds of compounds having different values of x in Formula (1), and are a powder mixture satisfying a relationship of x.sub.max-x.sub.min23 0.2, in a case where a maximum value of x is defined as x.sub.max and a minimum value of x is defined as x.sub.min, in two or more kinds of compounds having different values of x in Formula (1), and the application. In Formula (1), A represents at least one metal element selected from the group consisting of Sr, Ba, Ca, and Pb, and x satisfies 1.5≤x≤8.0.

AFe.sub.(12-x) Al.sub.xO.sub.19   Formula (1)

Methods for removing reduced sulfur compounds, such as hydrogen sulfide, from fluids employing a ferric iron salt that exhibits unusually high solubility in aqueous, alkaline solutions and has strong affinity for capture and oxidation of reduced sulfur compounds. Alkaline aqueous ferric iron salt and solutions thereof useful for removing reduced sulfur compounds from fluids and various methods of production of such salts and solutions. In addition, methods of regenerating the alkaline aqueous ferric iron salt solutions after capture of hydrogen sulfide or other reduced sulfur compounds, generally by exposure to oxygen in air. The alkali metal carbonate salt preferably comprises potassium carbonate and/or potassium bicarbonate. The alkaline aqueous ferric iron salt solutions generally comprise ferric ions, potassium ions, carbonate ions, and bicarbonate ions, optionally with one or more organic additives. In addition, aqueous-soluble, ferric iron salts and ferric iron containing solids prepared by removal of aqueous medium from solutions herein.

Methods for removing reduced sulfur compounds, such as hydrogen sulfide, from fluids employing a ferric iron salt that exhibits unusually high solubility in aqueous, alkaline solutions and has strong affinity for capture and oxidation of reduced sulfur compounds. Alkaline aqueous ferric iron salt and solutions thereof useful for removing reduced sulfur compounds from fluids and various methods of production of such salts and solutions. In addition, methods of regenerating the alkaline aqueous ferric iron salt solutions after capture of hydrogen sulfide or other reduced sulfur compounds, generally by exposure to oxygen in air. The alkali metal carbonate salt preferably comprises potassium carbonate and/or potassium bicarbonate. The alkaline aqueous ferric iron salt solutions generally comprise ferric ions, potassium ions, carbonate ions, and bicarbonate ions, optionally with one or more organic additives. In addition, aqueous-soluble, ferric iron salts and ferric iron containing solids prepared by removal of aqueous medium from solutions herein.