China Nonferrous Metallurgy

The stability of hydrolytic seeds is crucial for the hydrolysis process in the sulfate process for titanium dioxide production. Using industrial titanyl sulfate solution as raw material， hydrolysis seeds were prepared by alkali neutralization method. The effects of alkali-to-TiO2 ratio， aging temperature， and aging time on seed stability were systematically investigated， and the intrinsic relationship between process-structure-performance was explored by using multiple analytical methods， and the following main conclusions were obtained. The alkali-titanium ratio， curing temperature and curing time all affect the stability of the hydrolyzed seed crystal by affecting the reaction process and system properties. Appropriate increase of these process parameters can promote the nucleation rate and growth rate of the crystal nucleus； The optimum process parameters for the hydrolysis of industrial titanium liquid are as follows： alkali-titanium ratio 14%， curing temperature 95℃， curing time 18-21 min， stirring speed 300 r/min. Under these conditions， the stability of seed crystal is stable in the qualified range of 100-130 mL， the hydrolysis rate is 10. 16%， and the repeatability of the verification experiment is good. The particle size of the hydrolyzed seed is in the range of 21±6. 5 nm， and the particle size distribution is narrow， which ensures the high stability and activity of the seed. After optimization， the Ti—O bond of the hydrolysis seed is strengthened， the cluster structure is densified， and the Ti—S—O coordination structure is improved， significantly enhancing surface stability. This study provides a novel strategy for preparing highly stable seeds for titanium dioxide production by the sulfate process.