25 сентября, 2015 
Pokraskin The quality of the TiO2 pigment is influenced by various factors. Reaction temperature, excess oxygen, and rheologic conditions in the reactor affect particle size and
size distribution. Therefore, sophisticated conditions must be established for every reactor. Caking of the TiO2 on the walls of the reactor leads to deterioration of quality and reduced on-stream time.
The presence of water and/or alkali compounds during combustion of the TiCl4 results in the generation of nuclei, which promote the controlled formation of finely divided pigment particles with high scattering power [2.40]. Additives may be added directly to the oxygen or can be produced by the combustion of hydrogen-containing materials.
The presence of AlCl3 promotes the formation of rutile and a more finely divided pigment. It is added in amounts of up to 5 mol%. Many methods have been proposed for rapidly generating and directly introducing the AlCl3 vapor into the TiCl4 vapor. Addition of PCl3 and SiCl4 suppresses rutile formation, so that anatase pigment is obtained [2.41]. However, pigments of this type have not appeared in the market.
2.1.3.4
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