The invention belongs to the technical field of
nonferrous metal extraction. The invention provides a method for efficiently extracting
lithium from
lithium-rich aluminum
electrolyte waste residues and preparing
anhydrous aluminum fluoride. According to the method, HF gas generated by curing and volatilizing concentrated
sulfuric acid is subjected to dust removal and
impurity removal and then directly makes contact with an aluminum-loaded organic phase to prepare
anhydrous AlF3, the purity of the synthesized
anhydrous AlF3 is high, the prepared anhydrous AlF3 can be returned to the
aluminum electrolysis process to serve as a cosolvent, and cyclic utilization of aluminum and
fluorine is achieved. According to the method, the
lithium resource in the lithium-rich aluminum
electrolyte waste residues is recycled in the form of Li2CO3, the recycling rate is high, the product purity is high, and high
economic benefits are achieved. According to the method,
sodium dimethyl
dithiocarbamate solution is used as a precipitator to deeply purify and remove
calcium,
magnesium and aluminum, the
impurity element removal effect is thorough, and raw materials are prepared for the step of precipitating lithium in
sodium carbonate. In the treatment process of the lithium-rich aluminum
electrolyte waste residues, various components can be efficiently recycled, and new
pollution is not generated while waste materials are fully recycled.