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How did you get the titanium in your hand (2)? Several routes for preparing titanium tetrachloride from titanium concentrate

Titanium concentrate contains a large amount of impurities. Before preparing sponge titanium, we need to first prepare it as an intermediate product, titanium tetrachloride.
For the production process of titanium tetrachloride, although there are slight differences in the process flow among countries, it mainly consists of three steps: batching, chlorination, and refining.
1. Ingredients
The qualified titanium rich material from the high-level silo and the crushed and dried petroleum coke are added to the screw conveyor according to a certain proportion of ingredients in the batching section. After initial mixing, they are sent to the flow flower machine, and then sent to the chlorination section by air. After cyclone and bag dust collection, they are discharged into the mixing silo for use in the chlorination furnace.
2. Chlorination
The chlorination process mainly includes three methods: boiling chlorination, molten salt chlorination, and vertical furnace chlorination. Boiling chlorination is currently the main method for producing titanium tetrachloride (adopted by China, Japan, and the United States), followed by molten salt chlorination, while vertical furnace chlorination has been phased out. Boiling chlorination generally uses high-grade titanium rich materials with low calcium and magnesium content as raw materials, while molten salt chlorination can use materials with high calcium and magnesium content.
① Boiling chlorination
Boiling chlorination, also known as fluidized chlorination, is a production method widely used in China in recent years and is also widely used in countries such as the United States and Japan.
The operating temperature for fluidized chlorination is generally controlled between 1000-1050 ℃, at which point the rich titanium material undergoes carbon chlorination reaction. In actual production, accurate carbon ratio, chlorine to material ratio, mixture particle size, and appropriate chlorination temperature are key factors affecting boiling chlorination.
② Molten salt chlorination
Molten salt chlorination is more common in countries such as Russia, and some manufacturers in China also use it.
The disadvantages are: (1) complex operation and equipment, high labor intensity, difficulty in recovering and processing a large amount of molten salt, and easy to cause secondary pollution; (2) The furnace lining material [ii] has a shorter lifespan due to erosion by high-temperature molten salt; (3) Not suitable for the production of large-scale chlorinated titanium dioxide products.
3. Refined
The principle of producing titanium tetrachloride is to remove high boiling point impurities through distillation; The refining process mainly involves separating impurities from the crude TiCl4 produced by chlorination, purifying it into high-quality TiCl4 for use in the next production process.
Coarse TiCl4 is a reddish brown or pale yellow turbid liquid, containing impurities mainly in gas, liquid, and solid phases. The refining process first separates low boiling point impurities, and then separates high boiling point impurities. Impurities with boiling points similar to TCL4 are difficult to separate, and this process is also known as vanadium removal.
The crude titanium tetrachloride refined vanadium removal methods currently used in industrial production include copper wire vanadium removal method, H ₂ S vanadium removal method, aluminum powder vanadium removal method, mineral oil vanadium removal method, etc., which remove low boiling point impurities through distillation.
① Copper wire vanadium removal method
Copper wire vanadium removal can obtain high-quality titanium tetrachloride, but it is an intermittent operation and cannot be produced continuously. The regeneration and washing of failed copper wire balls is troublesome, labor-intensive, and prone to environmental pollution. It is also not convenient to recover vanadium from it. Moreover, this method is not suitable for manufacturers of sponge titanium and titanium dioxide with high vanadium content and large-scale production.
② H ₂ S vanadium removal method
H ₂ S is a highly toxic, flammable, and explosive gas with a foul odor. Therefore, the use of H ₂ S for vanadium removal has poor working conditions and complex processes. But H ₂ S has good vanadium removal effect and low cost. It is more suitable for large-scale enterprises to use this method to remove vanadium.
③ Vanadium removal method from mineral oil
This method is widely used in the United States and Japan. Mineral oil is added to titanium tetrachloride, and a small amount of organic matter is added to the crude TiCl4 solution under heating conditions. The organic matter dissolved in TiCl4 carbonizes at high temperatures (generally 120-138 ° C) and gradually decomposes into highly dispersed and highly active new ecological fine carbon particles. At the same time, other chloride impurities in the crude TiCl4 have a catalytic effect on the decomposition of organic matter. This new ecological fine carbon particle can be selectively adsorbed or reduced to precipitate in solid form. The vanadium removal process produces a polymerized and viscous residue, which is easy to form scars on the heater wall. The process is simple, the equipment is few, and the cost of vanadium removal is low.
④ Aluminum powder vanadium removal method
The essence of aluminum powder vanadium removal is TiCl4 vanadium removal. Under the condition of AlCl3 as a catalyst, aluminum powder can reduce TiCl4 to TiCl3, and this low valent titanium chloride is a strong reducing agent.
This method is mostly adopted by Russia, and the products produced have high purity. Titanium tetrachloride is treated with strong reducing agents, and many impurities are reduced to low-priced substances. This method produces a small amount of vanadium removal residue, which is easy to separate from TiCl4 and recover vanadium from the vanadium slag produced by vanadium removal. The cost of vanadium removal is low, and it is a vanadium removal method suitable for sponge titanium production.
After obtaining high-purity TiCl4, the next step is to prepare one of the key raw materials for titanium alloys, sponge titanium!
Finally, titanium metal sets off from the ore and takes another step forward towards the titanium alloy material in your hand!

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