Synthesis method for bis(fluorosulfonyl)imide salt

Abstract

The invention discloses a synthesis method for a bis(fluorosulfonyl)imide salt, wherein the method comprises the following steps: (one) under the protection of nitrogen, dissolving a bis(chlorosulfonyl)imide salt in a nonprotic organic solvent to obtain a bis(chlorosulfonyl)imide salt organic solution; (two) under a stirring condition, adding an excess compound fluridizer into the organic solution, then heating to a temperature being 8 DEG C-20 DEG C higher than an organic solvent boiling point temperature, and making the bis(chlorosulfonyl)imide salt to undergo an effective fluorination reaction in the organic solvent, wherein the compound fluridizer is selected from at least two substances of antimony trifluoride, potassium fluoride, zinc fluoride and aluminum fluoride; (three) after the reaction is finished, filtering the reaction liquid, and concentrating the filtrate to obtain a concentrated solution; and (four) crystallizing the concentrated solution, filtering, drying, and thus obtaining the high-purity bis(fluorosulfonyl)imide salt. The synthesis method has the advantages of simple operation, high product productive rate, no toxic reagent to pollute the environment, and high purity of the product, and is suitable for large-scale production in industry.

Description

technical field [0001] The invention belongs to halogen exchange fluorination synthesis and relates to a preparation method of alkali metal salt of bisfluorosulfonimide. Background technique [0002] Fluorine is the most electronegative element known so far. The introduction of fluorine atoms into molecules can cause drastic changes in its physical and chemical properties, resulting in many strange properties in terms of optical, electrical and magnetic properties. At present, fluorine-containing compounds have shown great research value and economic value in the research and application of energy storage electronic materials and biological materials. Some fluorine-containing compounds have ultra-high electrical conductivity, which makes them have important applications in electrochemical energy storage materials and devices such as secondary lithium-ion batteries and supercapacitors. For example, lithium bistrifluoromethylsulfonylimide (LiTFSI), lithium tetrafluoroborate (...

AI Technical Summary

Problems solved by technology

[0010]J.K.Ruff et al. used AsF3 fluorinating agent in the process of fluorinating bischlorosulfonimide, which used highly toxic As element, not Suitable for industrial production (J.K.Ruff et al, Inorg.Synth. 1968, 11, 138); the antimony trichloride contained in the fluorinating agent compound fluorinating agent used by B.Krumm et al. has a very strong sublimation property , can not go out in the late stage of the reaction (B.Krumm et al, Inorg.Chem.1998, 37, 6295); although Zhou Zhibin and others use potassium carbonate to neutralize antimony trichloride, it will lead to difluorosulfonimide after neutralization The salt cannot be separated (Zhou Zhibin et al., application number: CN 102786451 A)

A.Hammami et al. used excess potassium fluoride (KF) and dichlorosulfonimide to react in an organic solvent to directly prepare the potassium salt of H[FSI]; this preparation route not only generates highly toxic gas HF, but also reacts excessively Since the potassium salt of the product KF and the product H[FSI] is insoluble in the organic solvent, the reaction system will coagulate into blocks, and the separation and purification operations are difficult and cumbersome, etc. (A.Hammami et al, US 2007043231, 2007)