METHOD OF PROCESSING SPHENE Russian patent published in 1997 - IPC

FIELD: production of inorganic substances. SUBSTANCE: invention relates to producing titanium- containing substances applicable in leather, varnish-and-dye industries, in production of paper, cosmetics, etc. To titanium- containing solution, ammonium sulfate is added in weight proportion 1:(3-5) to titanium dioxide. Mixture is aged for 2-5 h, whereupon precipitate is separated and, to filtrate, crushed mica is added. Resultant mixture is heated to 40-60 C, kept for 2-4 h and then for another 2-6 h at 90-105 C followed by separating mica and baking it to yield pearl pigment. Calcium-silicate residue obtained after stripping sphene is pulped in water. Pulp is supplemented with soluble iron salt in amount corresponding to 5-25% Fe₂O₃ related to residue weight. Mixture is neutralized until iron is fully precipitated. Precipitate is filtered off and calcined to give iron- containing pigment. EFFECT: enhanced efficiency of process due to acceleration thereof and utilization of all principal intermediate products as well as liquid and solid wastes for production of valuable high-quality products.