Chlorination Preparation of Titanium White
Titanium white is a white pigment composed of titanium dioxide. Synthetic titanium white is a white powder produced by chlorination method. It is mainly used for producing paint products with good hiding performance, whiteness and durability. This paper will discuss the chlorination preparation process of titanium white.
Chlorination is an important method for producing titanium white. The raw material of titanium white is usually ilmenite, a mineral form of titanium dioxide. The primary process of chlorination preparation is the chlorination reaction of ilmenite in an alkaline solution, usually accompanied by oxygen blowing. Chlorination of titanium dioxide involves the oxidation of titanium in the ore with chlorine gas, and the production of titanium trichloride. It should be noted that the temperature of the chlorination reaction is 80-100°C.
After chlorination, a mixture of titanium trichloride and iron trichloride-hydrochloric acid solution is obtained. The iron content in the solution needs to be removed. Usually, the solution is desalted and a double-layer precipitation-dechlorination process is adopted. The iron content in the solution can be decreased to less than 0.004%. After desalination, the titanium trichloride is finally complexed with a metal alcohol to produce a titanium alkoxide.
The titanium alkoxide is then subjected to an oxidation-dedustration process to obtain a titanium alkoxide-hydroxychloride suspension. At this stage, the oxygen content in the suspension needs to be increased through oxygen blowing. Then, the titanium hydroxychloride suspension is further oxidized at a higher temperature to obtain a titanium white slurry, which is composed of rutile-titanium dioxide particles. The titanium dioxide suspension is then subjected to a filtration process to obtain the titanium white powder.
The obtained titanium white powder contains a certain amount of water and needs to be dried at a temperature of about 120°C. After drying, the titanium dioxide powder is completed by crushing and grading. The titanium dioxide powders obtained by this process have high purity and good hiding performance.
This article has introduced the chlorination preparation process of titanium white in detail. Chlorination method is an important method for producing titanium white. It has advantages of stable product quality, good hiding performance and low cost. Therefore, it is widely applied in the industrial production of titanium white.
