PREPARATION OF HIGHLY ACTIVE PHOTOCATALYST, TiO2 COMPOSITE POWDER BY COPRECIPITATION METHOD

摘要

PURPOSE: Provided is a preparation method of highly active photocatalyst, TiO2 composite powder whose optical activity is 2-4times higher than a conventional catalyst by coprecipitation method. CONSTITUTION: The photocatalyst TiO2 composite powder is prepared by the following steps of: (i) preparing a titanyl chloride solution by adding distilled water to TiCl4 and a metal compound containing transition metals substituting for Ti in the Ti-solution, wherein the metal compound is at least one compound selected from chloride, nitride and hydroxide of metals, such as AlCl3, NiCl2, FeCl3, NbCl2, ZrCl4 and CuCl2; (ii) mixing titanyl chloride solution and metal compound; (iii) reacting mixtures at 15-150deg.C for 2-20hrs to get precipitates such as rutile, anatase-rutile or anatase TiO2 powder(0.005-0.5micrometer); (iv) adding a neutralizer, 0.1-7M of ammonia or NaOH, to precipitates; (v) washing precipitates to remove Cl- and Na+ ions remaining in precipitates(TiO2), and drying TiO2 powder under 150deg.C. The resultant TiO2 composite powder contains 0.01-2mol% of metals, and anatase and rutile phase TiO2 in a volume ratio of 10/90-40/60.