Recovery of Titanium from Perovskite by Acid Sulfation.
Shirts-MB; Martin-DA; Peterson-AE
U S Patent 1985 Dec; (4):6 pages
The ca-containing ti ores of the perovskite type (with ca titanate) are mixed with excess h2so4 for leaching in a digester at 130-338 deg c. The sulfated residue is separated from excess h2so4 by filtration and leached with water at up to 150 deg c to obtain up to 200 g ti sulfate /l for separation from insoluble caso4. The purified ti sulfate in solution is processed by a hydrothermal precipitation to obtain tio2 suitable for pigment. Thus, perovskite ore concentrate (containing tio2 47, cao 26.2 and fe2o3 3.2%) 100 G was powdered to -100 mesh and treated with 96% h2so4 500 g in an autoclave at 300 deg c for 10 min. Sulfated residue 275 g was filtered from hot acid and leached with 500 ml of water to dissolve 92% of the ti for filtration separation from caso4. The resulting solution containing 56 g ti/l was processed by hydrothermal precipitation to obtain hydrous tio2.
U.S. Patent No. 4,562,049, Dec. 31, 1985