Abstract: There is described a process for preparing metal oxide particles which are substantially free of coarse tail from an oxidizing agent and a vaporous metal reactant in a flow reactor; comprising, (a) directing a flow of the metal reactant into a contacting region of the flow reactor; comprising (a) passing a flow of oxidizing agent through a high temperature zone of the flow reactor to form a flow of hot oxidizing agent and directing the flow of the hot oxidizing agent onto the contacting region of the flow reactor at a flow condition sufficient to form a reaction stream comprising a flow of hot oxidizing agent, a flow of metal reactant and a diffusive flow of the hot oxidizing agent and the metal reactant, the temperature of the hot oxidizing agent being at least sufficient to initiate oxidation of the metal reactant in the diffusive flow; (c) passing the reaction stream into a reaction zone of the flow reactor, while simultaneously introducing a flow of an upper cooling fluid substantially coaxially with the

Abstract: The invention concerns a process for the spheroidisation, densification and purification of powders through the combined action of plasma processing, and ultra-sound treatment of the plasma-processed powder. The ultra-sound treatment allows for the separation of the nanosized condensed powder, referred to as ‘soot’, from the plasma melted and partially vaporized powder. The process can also be used for the synthesis of nanopowders through the partial vaporization of the feed material, followed by the rapid condensation of the formed vapour cloud giving rise to the formation of a fine aerosol of nanopowder. In the latter case, the ultra-sound treatment step serves for the separation of the formed nanopowder form the partially vaporized feed material.

Abstract: There is described an apparatus for making metal oxide particles which are substantially free of coarse tail from an oxidizing agent and a metal reactant in a flow reactor. The apparatus can be a concentric tubular flow reactor comprising a substantially funnel-shaped reactant contacting region located adjacent to a reaction zone which is able to direct a flow of a hot oxidizing agent towards a flow of the metal reactant to form a reaction stream which flows downstream into a reaction zone, whereby the hot oxidizing agent of the reaction stream is able to surround the flow of metal reactant sufficient to prevent the metal reactant from contacting the wall of the reactant contacting region and forming scale on the wall.

Abstract: There is described an apparatus for making metal oxide particles which are substantially free of coarse tail from an oxidizing agent and a metal reactant in a flow reactor. The apparatus can be a concentric tubular flow reactor comprising a substantially funnel-shaped reactant contacting region located adjacent to a reaction zone which is able to direct a flow of a hot oxidizing agent towards a flow of the metal reactant to form a reaction stream which flows downstream into a reaction zone, whereby the hot oxidizing agent of the reaction stream is able to surround the flow of metal reactant sufficient to prevent the metal reactant from contacting the wall of the reactant contacting region and forming scale on the wall.

Abstract: There is described a process for preparing metal oxide particles which are substantially free of coarse tail from an oxidizing agent and a vaporous metal reactant in a flow reactor; comprising, (a) directing a flow of the metal reactant into a contacting region of the flow reactor; comprising (a) passing a flow of oxidizing agent through a high temperature zone of the flow reactor to form a flow of hot oxidizing agent and directing the flow of the hot oxidizing agent onto the contacting region of the flow reactor at a flow condition sufficient to form a reaction stream comprising a flow of hot oxidizing agent, a flow of metal reactant and a diffusive flow of the hot oxidizing agent and the metal reactant, the temperature of the hot oxidizing agent being at least sufficient to initiate oxidation of the metal reactant in the diffusive flow; (c) passing the reaction stream into a reaction zone of the flow reactor, while simultaneously introducing a flow of an upper cooling fluid substantially coaxially with the

Abstract: The invention concerns a process for the spheroidisation, densification and purification of powders through the combined action of plasma processing, and ultra-sound treatment of the plasma-processed powder. The ultra-sound treatment allows for the separation of the nanosized condensed powder, referred to as ‘soot’, from the plasma melted and partially vaporized powder. The process can also be used for the synthesis of nanopowders through the partial vaporization of the feed material, followed by the rapid condensation of the formed vapour cloud giving rise to the formation of a fine aerosol of nanopowder. In the latter case, the ultra-sound treatment step serves for the separation of the formed nanopowder form the partially vaporized feed material.