Method for preparing battery-stage anhydrous lithium chloride

Abstract

The invention provides a preparation method of a battery grade lithium chloride, comprising: (1) calcium chloride is added into the acid clinker extracting solution of lithium concentrate - lithium sulfate solution, the PH value of the solution is regulated by NaOH to eliminate Fe and Mg, and the precipitation of CaSO4.2H2O, Fe(OH)3 and Mg(OH)2 and lithium chloride solution are obtained after the reaction; (2) the products of step (1) are filtered and cleaned to eliminate the precipitation of CaSO4.2H2O, Fe(OH)3 and Mg(OH)2, and the LiCl solution, i.e. a conversion solution is prepared; (3) the conversion solution is added with BaCO3, and filtered and cleaned after the reaction, to eliminate SO42- and Ca2+, and the LiCl concentrate liquid 1 is prepared; (4) the LiCl concentrate liquid is added with HCL and boiled to eliminate CO32-, and added with NaOH solution to back blend PH, then be evaporated, condensed, cooled, crystallized and separated, and the LiCl concentrate liquid 2 is obtained; (5) the LiCl concentrate liquid is added with refining agent, and filtered and cleaned after the reaction to eliminate Na, and the LiCl finish liquid is prepared, the LiCl finish liquid is condensed and dried, and finally the battery grade LiCl product is prepared. The invention has simple production process and can be easily operated.

Description

Technical field: [0001] The invention relates to a preparation method of battery-grade anhydrous lithium chloride. Background technique: [0002] Lithium chloride is an important lithium salt product, in addition to being used in air-conditioning dehumidifiers, bleaches, insecticides, synthetic fibers, pharmaceutical industry, lithium batteries, solar cells, metal alloy welding agents or fluxes, polymer material synthesis As a catalyst, another very important use is to produce metal lithium by molten salt electrolysis. At present, metal lithium has not only become one of the most important strategic substances in national defense, but also an important metal element closely related to human daily life. Lithium metal and its alloys and compounds are widely used in atomic energy industry, metallurgical industry, battery, glass, ceramics, chemical industry, aerospace industry manufacturing and other fields. In recent years, lithium chloride has also begun to be widely used in...

AI Technical Summary

Problems solved by technology

[0012] However, there are some deficiencies in this method: (1) This method does not propose a reliable method for removing Na + , Mg 2+ , Fe 3+ , CO 3 2- , acid insolubles and other impurities, resulting in LiCl product quality can not be guaranteed; (2) the method removes Ca with lithium carbonate solution 2+ 、Ba 2+ , because the solubility of lithium carbonate is low, a large amount of water will be brought in, resulting in increased evaporation in the subsequent process and a waste of energy; (3) under the Li concentration described in it, CO 3 2- Ba 2+ Completely removed, resulting in high content of barium chloride in lithium chloride products, affecting product quality

[0013] In addition, the methods of producing LiCl such as liquid membrane method, ion exchange adsorption method, salting out method, flotation method and extraction method are still in the laboratory research stage, and the industrial implementation is not yet mature.

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