Study on the effect of the particle size of hydrolysis seeds prepared by industrial titanyl sulfate solution

With industrial titanyl sulfate solution as raw material, the hydrolysis seeds were prepared by sodium hydroxide solution neutralization method, which is commonly used in titanium pigments production by sulfuric process. And under different raw material indexes and process parameters, the changes of the seeds particle size stability were also investigated. Then the seeds with different particle sizes were used for hydrolysis, and the correlation between particle size of seeds and that of metatitanic acid was studied. Furthermore, under the condition of fixed salt treatment, the influence on the particle size and reducing power of the subsequent rutile titanium white was studied. The results show that with the increase of TiO₂ concentration, F value, Fe/TiO₂ of titanyl sulfate solution and NaOH solution concentration, the particle size of seeds increases under the same stability. With the increase of the ratio of NaOH/TiO₂, the preheating temperature of titanyl sulfate solution and NaOH solution, the particle size of seeds decreases under the same stability. With the increase of aging time, the stability of seeds decreases and the particle size of seeds increases. With the increase of seeds particle size, D₅₀ and span of metatitanic acid obtained by hydrolysis gradually decreases, and the grain size of metatitanic acid slightly increases. The SEM average particle size and standard deviation of the corresponding rutile titanium white sample gradually decreases, while the Tcs and Scx of the sample increases.