Preparation method of titanium dioxide according to chlorination method

Abstract

The invention relates to a preparation method of titanium dioxide, and discloses a preparation method of titanium dioxide according to a chlorination method. The preparation method is mainly characterized in that chlorine gas separated from a filter is cooled by a cooler, and then compressed by a chlorine compressor, the compressed low-temperature chlorine gas is returned to a cooling pipe through a connecting pipe, and is mixed with a mixture, obtained through oxidation reaction, in the cooling pipe, so as to cool the mixture, obtained through oxidation reaction, in the cooling pipe. The preparation method has the advantages that 1) the temperature of the mixture obtained after the oxidation reaction is rapidly reduced; 2) no new impurity is introduced into the mixture obtained through oxidation reaction; 3) the produced titanium dioxide is good in particle dispersity, uniform in particle size, and applicable to high-quality pigment preparation.

Description

technical field [0001] The invention relates to a production process of titanium dioxide, in particular to a production process of chlorination titanium dioxide. Background technique [0002] Titanium dioxide is a white inorganic pigment with the best opacity, best whiteness, brightness and non-toxic properties. It is recognized as the best white pigment in the world. It is widely used in coatings, plastics, papermaking, Printing ink, chemical fiber, rubber, cosmetics and other industries. [0003] The production of titanium dioxide by the chlorination method is mainly to mix the titanium-rich raw material with petroleum coke, and then carry out chlorination reduction reaction in the chlorination furnace to form a mixture containing titanium tetrachloride, and the mixture from the top of the chlorination furnace passes through the cyclone dust collector Separation of slag and dust to obtain crude titanium tetrachloride; make the VOCl contained in the crude titanium tetrachl...

AI Technical Summary

Problems solved by technology

"Experiments have shown that simply using circulating water to cool the oxidation reaction mixture can only reduce the temperature of the mixture to 400°C to 500°C with a reasonable cooling pipe length. If cooling to a lower temperature is required, an extra-long Cooling pipe, but this will have problems such as easy damage to the equipment and too long cooling time

And the titanium dioxide particles produced by the oxidation reaction must be cooled rapidly, otherwise the aggregation of titanium dioxide particles at high temperature will lead to problems such as excessive particle size or uneven particle size distribution, which will seriously affect the quality of the pigment

[0009] However, if the mixture at 400°C to 500°C is introduced into a bag filter for filtration, since the mixture contains a large amount of high-temperature chlorine gas, it is more demanding for the material selection of the filter flow parts for separating the oxidation reaction mixture, and nickel is required for many key components. Base alloys, even then, are not immune to the risk of production shutdowns due to filter damage due to high temperatures

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