Study On Production Process Of Titanium Dioxide By TiCl₃ Hydrolysis

Titanium dioxide is an important white pigment.Single factor experiment was established to study on production process of titanium dioxide by TiCl3 hydrolysis,in which XRD,SEM and other detecting means were used.The specific research content was as follows:(1)Hydrolysis conditions were important factors in the hydrolysis process,which directly affected the quality of products.Factors affected hydrolysate were exploratory analysed in this paper,mainly including additives and hydrolysis time.The study found that with the dosage of(NH4)2SO4 and K2SO4 increasing,the particle size of hydrolysate increase.The ammonia was not conducive to control the size of hydrolyzate.With the hydrolysis time increasing,the particle size of hydrolysate increase.(2)The influence of hydrolysis condition on hydrolysate was invesitigated in this paper.The study found that the influence of(NH4)2SO4 and hydrolysis time on hydrolysate was the same as the exploratory stage.With the water-alcohol ratio increasing,the size of hydrolyzate decrease.With the concentration of TiCl3 solution increasing,the size of hydrolyzate decrease.The optimum process parameters for the hydrolysis of pure TiC13 solution were as follows:(NH4)2SO4 was 1 g,the ratio of water-alcohol was 5/1,the concentration of TiCl3 solution was 10.87 g/L,the hydrolysis time was 20 min,the average size of hydrolyzate was 100 nm.(3)Based on the principle of hydrolysis,impurity ions could affect the particle size of the hydrolyzate.The influence of impurities(Fe2+?Mn2+?V5+)on hydrolysate was invesitigated in this paper.The results showed that with the addition of impurity ions,the particle size of hydrolyzate decrease and the whiteness become worse.The optimum process parameters for the hydrolysis process of TiC13 solution with impurities were as follows:(NH4)2SO4 was 4 g,the ratio of water-alcohol was 5/1,the concentration of TiCl3 solution was 10.87 g/L,hydrolysis time was 20 min,the average particle size of hydrolysis product was 90 nm,the whiteness was 72.1%.(4)The condition of calcination directly affected the quality of titanium dioxide.The influence of calcination temperature and calcination time on products were invesitigated in this paper.The results showed that with the calcination intensity increasing,the particle size of the product increase,the conversion rate of crystal form increase,the value of whiteness increased and then decreased.The optimum process parameters were as follows:calcination temperature was 750?,calcination time was 1.5 h,the average particle size of product was 325 nm,the content of TiO2 was 92%,the whiteness was 74.1%,the value of R was 18%.(5)Compared with indicators of R-960 titanium white paint of DuPont Corporation:the average particle size was 350 nm,the content of TiO2 was 89%,the whiteness consulted sample.The indicator of this experiment was as follows:the average particle size was 325 nm,the content of TiO2 was 92%,the whiteness was 74.1%,the value of R was 18%.