Fused salt chlorination production technology of low-impurity titanium tetrachloride

Abstract

The invention relates to a fused salt chlorination production technology of low-impurity titanium tetrachloride. The fused salt chlorination production technology comprises the following steps: when producing titanium chloride through a fused salt chlorination method, collecting dust from high-temperature titanium chloride gas which is generated in a fused salt chlorination furnace and contains chloride impurities through a dust collector; then enabling the gas to enter an eluting tower and eluting with titanium chloride liquid; arranging a water spraying nozzle at the tower top of the elutingtower; introducing chlorine gas and enabling the water spraying nozzle to spray water; carrying out a hydrolysis reaction on the water entering the eluting tower with NaAlCl4 and NaFeCl4 low-melting-point coordination compounds and AlCl3 entrained in the titanium chloride gas to generate aluminum oxide and iron oxide; enabling the aluminum oxide and the iron oxide to enter an eluting groove of the eluting tower along with the titanium chloride and mixing into mud; and then returning the mud in the eluting groove back to the dust collector and carrying out dust collection. The fused salt chlorination production technology of the low-impurity titanium tetrachloride has the advantages that the NaAlCl4 and NaFeCl4 low-melting-point coordination compounds in a side reaction can be removed, anda fused salt chlorination reactor system is enabled to stably operate for a long time.

Description

technical field [0001] The invention relates to a chlorination production process of low-impurity titanium tetrachloride molten salt. Background technique [0002] At present, large-scale molten salt chlorination production technology is a mature technology in China, and the alumina component in the titanium-rich material will be chlorinated to form AlCl in the process of carbon chlorination. 3 , The chlorination rate is usually above 50%. AlCl 3 It is a layered structure in the solid state and will convert to Al when it is close to its melting point temperature 2 Cl 6 The molecular structure of the dimer vapor molecules volatilize into the gas phase; when the temperature rises further, the dimer molecules decompose into AlCl 3 molecular. In molten salt chlorination system, FeCl 3 Behavior with AlCl 3 similar. In the molten salt chlorination reactor, the product AlCl 3 , FeCl 3 It may form a chloride complex NaAlCl with relatively low saturated vapor pressure with ...

AI Technical Summary

Problems solved by technology

Since the crude titanium chloride underflow slurry produced by leaching in the leaching tower is directly returned to the dust collection or chlorination system, it will be gasified again, thereby continuously circulating and accumulating in the chlorination-dust collection-leaching system, which not only increases the The burden on the system can also easily cause problems such as system wall formation, partial liquefaction of dust collection slag, and scaling of heat exchangers, which will affect the continuity and stability of chlorination operation

In addition, NaAlCl 4 , NaFeCl 4 and a small amount of AlCl 3 It will also affect the follow-up TiCl 4 Refining and production of sponge titanium have adverse effects, and as a very acidic Lewis acid, it is highly corrosive to steel equipment

It has caused great difficulties to stabilize the production cycle of titanium chloride products