METHOD OF PROCESSING SPHENIC CONCENTRATE Russian patent published in 2002 - IPC

FIELD: processing of titanium-containing raw material. SUBSTANCE: sphenic concentrate is decomposed with 30-50% sulfuric acid at 70-90 C in the presence of fluorine ion in amount of 0.25-1 mole/mole of titanium. Solid residue is separated. Titanium-containing solution is treated with phosphoric acid to deposit product in the form of titanium phosphate. Solid residue is washed with acidified water at S: L ratio of 1: 1.3-2.6. The resulting wash solution is recycled to concentrate decomposition stage. Fluorine ion is added in the form of hydrofluoric acid or fluosilicic acid or soluble salts thereof. Solution resulting from decomposition of titanium phosphate is recycled to concentrate decomposition stage. EFFECT: greater efficiency of method due to process temperature lowered by 15-40% and high (80-88%) degree of recovery of titanium into solution. 3 cl, 5 ex _