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: 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: The present invention provides a process for preparing an aqueous solution of FeCl.sub.3. The process involves the steps of: (a) reacting an ore material comprising titanium and iron with chlorine and coke to form a metal chloride vapor stream comprising titanium tetrachloride, ferrous chloride, ferric chloride and unreacted coke and ore solids; (b) cooling the metal chloride vapor stream to a temperature in the range of 350 to 500.degree. C. to condense at least some of the ferrous chloride; (c) separating the condensed ferrous chloride and the unreacted coke and ore solids from the metal chloride vapor stream; (d) cooling the metal chloride vapor stream to a temperature in the range of 180 to 240.degree. C. to form a precipitate comprising ferric chloride; and (e) adding the precipitate to water to form an aqueous solution comprising ferric chloride. The resulting aqueous solution has a high FeCl.sub.3 content, and can be used in wastewater treatment applications.