METHOD FOR PREPARING LITHIUM FLUOROSULFATE USING ORGANIC METAL LITHIUM REAGENT

摘要

Disclosed in the present invention is a method for preparing lithium fluorosulfate using an organic metal lithium reagent, comprising the following steps: (1) using an organic metal lithium reagent as a lithium source, and at a low temperature with perfluorohexane as a solvent, slowly mixing with fluorosulfuric acid and reacting to obtain a lithium fluorosulfate crude product. The crude product is washed five times using the reaction solvent. (2) Performing decompression and draining on the crude product, and then adding the product into a poor organic solvent of lithium fluorosulfate and washing three times, and then vacuum drying the poor organic solvent to obtain a solid. (3) Adding carbonate-ester, -nitrile, and -alcohol organic solvents to the solid for extraction, filtration, and concentration, and adding a low-polarity aprotic solvent to the concentrated solution for static crystallization. (4) Crystal re-filtration, and vacuum drying to obtain a lithium fluorosulfate product. In the above preparation steps, anhydrous operations are performed under the protection of an inert gas. The preparation method provided in the present invention can be used to prepare lithium fluorosulfate and features high yield and stable product quality, and can further effectively reduce the content of such impurities as potassium ions, sodium ions, calcium ions, fluorine ions, sulphate radical ions, and water in the product.