Abstract: Titanium dioxide, in the form of discrete, solid substantially spherical particles of a substantially uniform shape and size, is obtained by providing an aerosol comprising discrete liquid particles of a hydrolyzable titanium compound, contacting the aerosol with water vapor in dynamic flow to hydrolyze the liquid titanium (IV) compound to titanium dioxide, and recovering the desired product.

Abstract: An improved process is described for recovering TiO.sub.2, useful as a white pigment, from ilmenite-type ores, including the steps of digesting the ore with aqueous hydrofluroic acid, separating out iron impurities from the resulting solution, precipitating hydrated titanium dioxide from the iron-free solution with ammonium hydroxide, and calcining the precipitate to obtain pigmentary TiO.sub.2, wherein the improvement comprises subjecting aqueous solutions of by-product ammonium fluoride, formed in the process, to electrodialytic water-splitting to form an aqueous solution of ammonium hydroxide and an aqueous solution of hydrogen fluoride and recycling said aqueous ammonium hydroxide to the precipitation step and said aqueous hydrogen fluoride to the digestion step.

Abstract: A catalytic ilmenite reduction procedure is described which provides a magnetic fraction consisting of the iron and titanium values of the ilmenite ores and a non-magnetic gangue. The magnetic fraction, after solubilization of the reduced iron, provides beneficiated Rutile-type titania product with purity ranges from 80 to 95% depending on the grade of ilmenite starting material. The titanias are further purified by sulfation and a metathetical reaction to convert the titanyl sulfates to chlorides by CaCl.sub.2.

Abstract: A process for removing chloride impurities from TiO.sub.2 by injecting a gas selected from steam, air, nitrogen, or a mixture thereof, at a sonic or a supersonic velocity, a pressure of about 25-600 psi, and a temperature of about 140.degree.-650.degree. C., into the TiO.sub.2 to disperse it, and then separating the TiO.sub.2 from the gas and chlorides.

Abstract: There is provided a process and apparatus for the production of finely-divided metal and metalloid oxides by flame hydrolysis of corresponding metal and metalloid halides whereby burner fouling is minimized and burner fabrication is facilitated by transpiration of a fuel gas or vapor along the boundaries of each halide-containing stream as it is discharged from the burner into a reaction zone.

Abstract: A solution of active nuclei for the hydrolysis of titanium sulphate and for the rutilisation of titanium dioxide in the manufacture of titanium dioxide in tutile form in the method via sulphate is prepared by transforming titanium tetrachloride into a compound of the formula Ti(OH).sub.x Cl.sub.y, wherein x ranges from 1 to 3, y from 3 to 1 and x + y is equal to 4 by contact with steam in the vapor phase, and contacting the reaction products with an aqueous solution of sodium hydroxide to form an aqueous suspension of titanium hydroxide having a TiO.sub.2 content of from 10 to 30 grams/liter and a pH value of from 3 to 4.

Abstract: A carrier for a catalyst which is composed of particulate titanium dioxide having a hardness of at least 40, a bulk density of at least 0.8 grams per milliliter and a specific area of less than 5 square meters per gram. The carrier is particularly useful for supporting enzymes or vanadium pentoxide.

Abstract: Process for the production of a finely divided oxide of a metal or silicon by the hydrolytic conversion of a volatile corresponding metal halide or silicon halide in a flame, said process comprising feeding the volatile halide in a mixture with a combustible hydrogen-containing gas and air or oxygen to a burner provided with a mouth emitting a flame, burning the mixture in a fire tube to form a first portion of water vapor, said burner surrounded by an annular chamber forming a nozzle through which hydrogen is passed to keep the mouth of the burner free of attachments of solid substances, the quantity of oxygen or air being sufficient for the practically complete combustion of the combustible gas, and the quantities of oxygen or air and combustible gas being sufficient to produce the first portion of water vapor which will at least suffice for the hydrolysis of the volatile halides, and further wherein said flame is allowed to burn in an atmosphere consisting of gases containing a second portion of water vapo