35results about "Imidodisulfonic/nitrilotrisulfonic acid" patented technology

The invention relates to the field of lithium batteries and lithium capacitors, in particular to a preparation method for difluorosulfimide lithium salt and application of the difluorosulfimide lithium salt. The preparation method for the difluorosulfimide lithium salt, provided by the invention, comprises the following steps: (1) performing fluorination reaction: synthetizing midbody difluorosulfimide from dichlorosulfimide and hydrogen fluoride under the action of a catalyst; (2) performing reaction between the difluorosulfimide obtained in the step 1 and alkaline lithium, and performing solid-liquid separation after the reaction to obtain an LiFSI product. The preparation method for the difluorosulfimide lithium salt, provided by the invention, is low in cost, few in by-product and simple in post-treatment, and the quality and the purity of the product are ensured, therefore the preparation method which is capable of obtaining the high-quality and high-purity product and is economic and practical is provided; the preparation method is suitable for industrial production.

The invention provides a method for producing hydrogen bis(fluorosulfonyl)imide (HFSI) by reacting hydrogen bis(halosulfonyl)imide (HXSI) with hydrogen fluoride, where each X is independently a nonfluoro-halide, such as Cl, Br, or I.

A fluorination process for obtaining fluorinated compounds including at least one fluorosulfonyl group. More particularly, a process for preparing a fluorinated compound of formula (II), including at least one step of reacting a compound of formula (I) with anhydrous hydrofluoric acid in at least one organic solvent, in which R1 is equal to R2 except in the specific case where R1=Cl, then R2=F, and when R1 is equal to R2, R1 and R2 represent an electron-withdrawing group which has a Hammett parameter op of greater than 0, such as F, CF₃, CHF₂, CH₂F, C₂HF₄, C₂H₂F₃, C₂H₃F₂, C₂F₅, C₃F₇, C₃H₂F₅, C₃H₄F₃, C₃HF₆, C₄F₉, C₄H₂F₇, C₄H₄F₅, C₅F₁₁, C₃F₅OCF₃, C₂F₄OCF₃, C₂H₂F₂OCF₃, CF₂OCF₃, C₆F₁₃, C₇F₁₅, C₈F₁₇ or C₉F₁₉, and M represents a hydrogen atom, an alkali metal, an alkaline-earth metal or a quaternary ammonium cation.

The invention relates to a method for the preparation of bis(fluorosulfonyl)-imide, the method starts from bis(chlorosulfonyl)-imide or its respective derivatives, which is reacted with HF in the presence of chlorosulfonyl isocyanate, and uses a certain extraction step for extraction of bis(fluorosulfonyl)-imide from an aqueous solution; the invention is also useful for the preparation of certain salts of bis(fluorosulfonyl)-imide and its derivatives.

The invention discloses a method for electrochemical synthesis of lithium imidodifluorosulfonate. The preparation method comprises: regulating the temperature of an electrolytic tank to 0-18 DEG C, respectively taking two nickel plates as an anode and a cathode, adding a proper amount of anhydrous hydrofluoric acid into the electrolytic tank, and carrying out electrolysis; after the current in theelectrolytic tank is stabilized, adding a proper amount of imidodichlorosulfonate into the electrolytic tank, and after the imidodichlorosulfonate is dissolved, adjusting the working voltage of the electrolytic tank to 5-8 V; when the current is reduced to below 5 mA, taking out the solution in the electrolytic tank; distilling the solution taken out from the electrolytic tank under normal pressure to separate the imidodifluorosulfonate from the anhydrous hydrofluoric acid, and cooling to obtain the high-purity colorless liquid imidodifluorosulfonate; and reacting with lithium hydroxide, filtering, and re-crystallizing to obtain high-purity lithium imidodifluorosulfonate. According to the invention, water and chlorine ions are electrochemically pre-removed while fluorination is performedthrough electrochemistry without introduction of a metal halide as a catalyst, so that the method is simple in process, low in energy consumption and low in cost, and the prepared LiFSI is high in purity.

A composition containing: at least 99.75% by weight of bis(fluorosulfonyl)imide lithium salt; and acetic acid in a content by mass greater than 0 and less than or equal to 400 ppm. A process for preparing the composition, including a) step of preconcentrating a composition C1 including an organic solvent OS1, water and bis(fluorosulfonyl)imide salt, to give a composition C2 including: the lithium salt of bis(fluorosulfonyl)imide in a content ranging from 35% to 50% relative to the total weight of composition C2; water in a mass content of less than or equal to 500 ppm relative to the total mass of composition C2; said preconcentration step being performed at a temperature of less than or equal to 50° C.; b) a step of concentrating composition C2; c) an optional step of crystallizing the composition obtained in step b).