Impurity removing and refining technology for crude zirconium tetrachloride

Abstract

The invention discloses an impurity removing and refining technology for crude zirconium tetrachloride and belongs to the technical field of chemical engineering. Hydroxide can be one of sodium hydroxide, potassium hydroxide and calcium hydroxide; and the concentration of the sodium hydroxide is 30 to 60 percent. The impurity removing and refining technology comprises the following steps: adding the sodium hydroxide into the crude zirconium tetrachloride, enabling the sodium hydroxide to be in sufficient contact with the crude zirconium tetrachloride, and then carrying out sedimentation and solid separation to remove solid impurities in the crude zirconium tetrachloride. A method provided by the invention can effectively reduce the impurities such as aluminum trichloride and silicon tetrachloride in the crude zirconium tetrachloride, and the sodium hydroxide, the aluminum trichloride and the silicon tetrachloride react to form colloidal aluminum hydroxide and sodium silicate; and the colloidal aluminum hydroxide and sodium silicate are used as flocculating agents, so that the sedimentation speed of other solid impurities in the zirconium tetrachloride can be accelerated and the impurity removing efficiency is effectively improved. Compared with a traditional gravity sedimentation method, the impurity removing and refining technology for the crude zirconium tetrachloride has thebeneficial effect that the impurity removing efficiency can be improved by 30 percent or above.

Description

technical field [0001] The invention belongs to the technical field of chemical industry, and in particular relates to a process for removing impurities and refining crude zirconium tetrachloride. Background technique [0002] Zirconium tetrachloride is an important intermediate product in the production of zirconium white powder by chlorination. Zirconium white powder (TiO2) is a white pigment. As an important chemical product, it has excellent optical properties and pigment properties, high whiteness, strong hiding power, high decolorization power and easy dispersion, so it is widely used in coatings, Plastics, paper, ink, rubber and other fields. The production of zirconium white powder by the chlorination method has the advantages of short process flow, large production capacity, continuous production, easy realization of automatic control, stable product quality, less three wastes, and low energy consumption, so it has developed rapidly in recent years. [0003] Howev...

AI Technical Summary

Problems solved by technology

[0004] Traditionally, gravity settling is used to preliminarily remove large particles of solid impurities in crude zirconium tetrachloride. However, the rate of gravity settling is very slow, the production efficiency is very low, and it is difficult to remove the trichloride dissolved in crude zirconium tetrachloride. Aluminum, silicon tetrachloride and other impurities