Recovery of Titanium from Perovskite Using Sulfuric Acid Leaching.
Shirts-MB; Martin-DA; Petersen-AE
U S Patent 1985 Nov; (4):6 pages
Powdered perovskite ores are leached with a concentrated h2so4 for a maximum extraction of titanium. The solution is then filtered from insoluble caso4, heated to near the boiling point to precipitate titanium sulfates, and diluted with h2o to redissolve the titanium sulfates for purification. Hydrolysis of the final solution is suitable for manufacture of hydrous tio2 for synthetic rutile. Leach tailings are washed to recover residual h2so4. Thus, powdered perovskite concentrate 100 g (containing 28.2% Ti; -200 mesh) was leached at 190 deg c with 1,743 g of 85 vol% h2so4 and filtered after 40 min. The caso4-rich residue of 198 g was washed with 300 g of h2o. Acidic filtered liquor 1,605 g was heated to b.P. (211 Deg c) for 60 min. The resulting low-acid solution contained 95% of the ti at 190 g/l and was hydrolyzed to precipitate hydrated tio2. In a similar leach of ore concentrate powdered to -100 mesh, the recovery of ti into solution reached a maximum in longer time at a lower temperature.
U.S. Patent No. 4,552,730, Nov. 12, 1985