A method for improving the crystallization properties of aluminum chloride mother liquor in the "one-step acid solution" process

Abstract

The invention provides a method for improving the crystallization property of aluminum chloride mother liquor in a one-step acid-soluble method technology. The method comprises the following steps: (1), diluting the aluminum chloride mother liquor with water till the mass concentration of aluminum chloride is 360 to 380g / L, so as to obtain an aluminum chloride mother liquor diluent; (2), performing centrifugation on the aluminum chloride mother liquor diluent when the mass content of insoluble particles is great or equal to 10g / L; performing evaporation and concentration on a solution containing aluminum chloride, so as to obtain an evaporated liquor; performing evaporation and concentration on the aluminum chloride mother liquor when the mass content of the insoluble particles is smallerthan 10g / L, so as to obtain an evaporated liquor; (3), leaving the evaporated liquor to stand, then adjusting the acidity of the evaporated liquor to be greater than 0.01 mol / L; (4), performing centrifugation on the evaporated liquor, so as to obtain aluminum chloride crystals and reflux liquid. The method improves the crystallization property of the mother liquor, increases the particle sizes andpurity of the aluminum chloride crystals, and provides a good condition for the next calcination process.

Description

technical field [0001] The invention relates to a method for improving the crystallization properties of aluminum chloride mother liquor in the "one-step acid dissolution method" process, and belongs to the technical field of post-treatment of the mother liquor in the "one-step acid dissolution method". Background technique [0002] In the prior art, in the process of producing aluminum chloride mother liquor crystallization using the "one-step acid dissolution method", the aluminum chloride solution is heated by a three-effect evaporator to obtain a concentrated aluminum chloride refined solution, so that the aluminum chloride refined solution reaches the Crystals are produced in a saturated state. After being sent to a centrifuge for solid-liquid separation, the separated solid-phase crystals are exported outside the three-effect evaporator for later use, and the remaining solid-liquid mixture is called aluminum chloride mother liquor after centrifugation. The aluminum mot...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a method for improving the crystallization performance of aluminum chloride mother liquor in the "one-step acid dissolution method" process, which solves the problems that the mother liquor replenishment evaporation system affects the normal crystallization process of aluminum chloride and the difficulty of solid-liquid separation, and effectively improves The crystallization performance of the aluminum chloride mother liquor is guaranteed, and the continuous and stable production cycle is guaranteed.

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