The process is to vaporize titanium alkoxide into vapor or atomize into tiny droplets through a nozzle, and then react with water vapor to synthesize monodisperse spherical nano-TiO 2 . Since the reaction temperature is not high, the prepared nano-TiO 2 is generally amorphous or anatase type, rutile To obtain nano-TiO 2, also need high temperature calcination. Its reaction formula is as follows:
nTi(OR) 4 (g)+4nH 2 O(g)===nTi(OH) 4 (s)+4nROH(g)
nTi(OH) 4 (s)===nTiO 2 ·H 2 O(s)+nH 2 O(g)
nTiO 2 ·H 2 O(s)===nTiO 2 (s)+nH 2 O(g)
Hu Liming et al. used low temperature nitrogen to cool the Ti(OC 4 H 9 ) 4 vapor carried by high temperature nitrogen to form submicron droplets, which were then reacted with water vapor to synthesize high purity and monodispersity at lower temperatures. The nano-TiO 2 particles are decomposed into a mixing section and a reaction section, and a cascade model of the full-mix reactor characterizing particle nucleation and growth is derived. The model explains the experimental phenomena and results well. Theoretical predictions and experimental studies show that the particle size of the product particles is related to the flow and mixing conditions in the reactor and the thermodynamic properties of the reaction system.
Japan's Soda Co., Ltd. and Idemitsu Kosan Co., Ltd. use nitrogen, helium, and air to remove carrier gases, and introduce titanium alkoxide vapor into the reaction zone of the reactor for instantaneous mixing and rapid hydrolysis. The particle size and particle shape of the nano TiO 2 are adjusted by changing the residence time, molar ratio, flow rate, concentration, and reaction temperature of various vapors in the reaction zone. This preparation process can obtain amorphous nano-TiO 2 having an average primary particle diameter of 10 to 150 mm and a specific surface area of 50 to 300 m 2 /g. If titanium alkoxide vapor, water vapor and organic surface treatment agent are introduced into the reactor together, after the titanium alkoxide vapor is vapor-phase hydrolyzed to form nano-TiO 2 , the TiO 2 particles can be further subjected to an organic surface treatment, and the prepared nano-TiO 2 can be used. In the field of paints, polymer materials and other catalysts. This process is characterized by low operating temperatures, low energy consumption, low material requirements, and continuous production. The disadvantage is that the raw material cost is high and the rutile-type nano TiO 2 cannot be directly synthesized.
We have done chemical products for over 30years. Our main products include PVC Resin, CPE, TIO2, Pe Wax, Paraffin Wax, Stabilizer, Stearic Acid ETC.
