Process for producing dispersion of particles of rutile titanium oxide

摘要

The invention provides a process for producing an aqueous dispersion of particles of rutile titanium oxide, which comprises:
a first step in which after a chloride ion concentration of an aqueous solution of titanium tetrachloride is adjusted to 0.5 mole/L or more and less than 4.4 mole/L, the aqueous solution of titanium tetrachloride is heated at a temperature in a range of from 25° C. to 75° C. to hydrolyze the titanium tetrachloride, thereby obtaining a slurry containing the thus precipitated particles of rutile titanium oxide;a second step in which the slurry obtained in the first step is filtered and washed with water to remove water-soluble salts dissolved therein from the slurry;a third step in which the slurry obtained in the second step is subjected to a hydrothermal reaction in the presence of an organic acid;a fourth step in which the slurry obtained in the third step is filtered and washed with water to remove water-soluble salts dissolved therein from the slurry;a fifth step in which an acid is added to the slurry obtained in the fourth step to deflocculate the slurry, and the resulting slurry is subjected to wet dispersion treatment, thereby obtaining a dispersion; anda sixth step in which excess acid and water-soluble salts are removed from the dispersion obtained in the fifth step.

主权项

1. A process for producing an aqueous dispersion of particles of rutile titanium oxide, which comprises:
a first step in which after a chloride ion concentration of an aqueous solution of titanium tetrachloride is adjusted to 0.5 mole/L or more, and less than 4.4 mole/L, the aqueous solution of titanium tetrachloride is heated at a temperature in a range of from 25° C. to 75° C. to hydrolyze the titanium tetrachloride, thereby obtaining a slurry containing the thus precipitated particles of rutile titanium oxide; a second step in which the slurry obtained in the first step is filtered and washed with water to remove water-soluble salts dissolved therein from the slurry; a third step in which the slurry obtained in the second step is subjected to a hydrothermal reaction in the presence of an organic acid; a fourth step in which the slurry obtained in the third step is filtered and washed with water to remove water-soluble salts dissolved therein from the slurry; a fifth step in which an acid is added to the slurry obtained in the fourth step to deflocculate the slurry, and the resulting slurry is subjected to wet dispersion treatment, thereby obtaining a dispersion; a sixth step in which excess acid and water-soluble salts are removed from the dispersion obtained in the fifth step.