Method for removing low-melting-point complexes in side reaction in production of titanium chloride

Abstract

The invention relates to a method for removing low-melting-point complexes in a side reaction in production of titanium chloride. The method comprises the following steps: when the titanium chloride is produced by a fused-salt chlorination method, enabling high-temperature titanium chloride gas containing chloride impurities and generated in a fused-salt chlorination furnace to enter a leaching tower to be leached by titanium chloride liquid after dust collection by a dust collector; arranging a water spraying nozzle at the top of the leaching tower, enabling the water spraying nozzle to carryout water spraying by introducing chlorine gas, and carrying out a hydrolysis reaction on water entering the leaching tower with NaAlCl4 and NaFeCl4 low-melting-point complexes and AlCl3 entrained inthe titanium chloride gas to generate aluminium oxide and iron oxide; and enabling the titanium chloride to enter a leaching groove of the leaching tower and mix into mud, and then returning the mudin the leaching groove to the dust collector for dust collection. The method involved in the invention has the advantages that the NaAlCl4 and NaFeCl4 low-melting-point complexes in the side reactioncan be removed, and long-time stable operation of a fused-salt chlorination reactor system can be ensured.

Description

technical field [0001] The invention relates to a method for removing low-melting point complexes in side reactions in the production of titanium chloride. 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 saturate...

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