| abstract |
PURPOSE: To purify an inorganic compound suitable as electronic material, etc., by simple facilities efficiently and in high degree, by bringing a specific inorganic compound into contact with an ion exchange resin in an aqueous medium. n CONSTITUTION: A water-insoluble inorganic compound (e.g. metatitanic acid) containing a water-soluble ion as an impurity is washed with water once or more times, redispersed into an aqueous medium to give aqueous slurry. Then, the slurry is adjusted to a pH which is apart from the isoelectric point of precipitate in the slurry, brought into contact with ≥ equivalent based on the water-soluble ion in the slurry of strongly basic anion exchange resin and treated. Then, the pH of the slurry is adjusted in such a way that the pH is coincident with the isoelectric point to aggregate precipitate particles. Then, the ion exchange resin is removed from the slurry, the prepared cake of the precipitate is dried to give an inorganic compound having ≤0.01wt% water-soluble ion as the impurity. n COPYRIGHT: (C)1987,JPO&Japio |