Japan's Fuji Titanium Industry Company adjusted the PH to 0.6~2.0 in the aqueous solution of tetravalent titanium sulfate and titanium chloride, and the obtained sol formed spherical water-based sol in water and immiscible heating medium, and successfully prepared spherical particles with excellent strength and wear resistance. Japan's Okamura Oil Company prepared particles with a particle size of 5~8nm by a similar method.
It is also an important research method to prepare nano-titanium dioxide by hydrolysis of organic titanium. The key of this method is to control the molar ratio of specific alcohol to water, hydrolysis temperature and hydrolysis speed. In the reaction process, if the molar ratio of water to alkoxide is particularly large (not less than 20), anatase microcrystals can be precipitated through the hydrolysis reaction of titanium alkoxide. A series of nano-TiO _ 2 were prepared by gas-phase hydrolysis of titanium alkoxide by Japanese Caotian Company and Chu Guang Sheng Xing Company, and the particle size was mostly controlled at 65438±05 ~ 30nm. Mit uses laser to initiate the gas phase hydrolysis of titanium tetraisopropoxide to obtain transparent anatase titanium dioxide, which is transformed into rutile after high temperature treatment. Ding Xing, from Institute of Solid State Physics, China Academy of Sciences, used butyl titanate as raw material to hydrolyze in the presence of anhydrous ethanol to obtain anatase nanometer titanium dioxide. When the sample is heated above 550℃, mixed crystals of anatase and rutile appear, while the hydrolyzed powder without heat treatment is amorphous.
In addition, the traditional preparation methods, such as titanium tetrachloride hydrolysis and titanyl sulfate hydrolysis, are constantly improving and perfecting. Japan's Ishihara Company, Imperial Chemical Company and Finland's Kemira Company first dissolved ilmenite with sulfuric acid to obtain titanyl sulfate, and after hydrolysis, neutralization and depolymerization, 10~30nm transparent titanium dioxide was obtained.