METHOD OF PROCESSING TITANIUM-CONTAINING MINERAL STOCK Russian patent published in 1999 - IPC

FIELD: nonferrous metallurgy. SUBSTANCE: invention relates to production of high-purity titanium dioxide for various applications. Initial titanium-containing stock is fluoridated with ammonium hydrodifluoride at molar ratio 1:(4-5). Fluoridated product is heated to separate by sublimation volatile ammonium fluoride complexes of titanium from nonvolatile iron compounds, after which the former are condensed. Condensed sublimate is thermally treated in two steps to give titanium dioxide. Iron-containing sludge is processed into iron oxide or iron metal alloyed with admixtures present in raw material for further utilization as pigment (ochre) in heat-resistant anticorrosive coatings and in powder metallurgy. Method makes possible producing white-color octahedrite modification of titanium dioxide and high-purity fine silicon dioxide as additional commercial product. EFFECT: increased degree of utilization of raw material and. 6 cl, 2 ex