Method for producing a fluorine- and sulfur-bearing compound and salts thereof in an aqueous medium
The invention relates to a method for producing a fluorine- and sulphur-bearing compound of formula F—SO—R (I) or F—SO 2 —R (II), comprising the reaction, in the presence of water, of at least one salt providing a fluoride anion and at least one halgoenosulfoxide compound of formula X—SO—R′ (I0) from a halogenosulfonyl compound of formula X—SO 2 —R′ (II0), in which X is a halogen atom other than fluorine and R and R′ are each a group linked by a covalent bond to the sulphur atom, said bond linking the sulphur atom with a nitrogen atom. The invention also relates to a method for producing salts of a fluorine- and sulphur-bearing compound of formula F—SO—R (I) or F—SO 2 —R (II) which are advantageously used as electrolyte salts, as precursors of antistatic agents or as surfactant precursors.
1. A process for preparing a fluorine-containing and sulfur-containing compound of formula F—SO 2 —R (II), the process comprising the reaction, in the presence of water, of at least one salt providing a fluoride anion, wherein the salt providing a fluoride anion is potassium fluoride, and of a halosulfonyl compound of formula X—SO 2 —R′ (II0), where X is chlorine, R is an —NM′SO 2 F group, M′ being potassium, and R′ is an —NHSO 2 X group; wherein the H 2 O/KF mole ratio is from 2.3 to 2.8, the molar equivalent of KF is from 10 to 20.8, the reaction temperature is 50° C. to 100° C., and the reaction time is between 0.5 hr and under 10 hr.
2. The process as defined in claim 1 , further comprising: a step of liquid/liquid extraction, and then the implementation of a sequence comprising the steps of acidification, of recovery of the acid obtained and of neutralization.
3. The process as claimed in claim 1 , further comprising: a step of liquid/liquid extraction, and then the implementation of a cation exchange reaction.
4. The process for preparing at least one salt of a fluorine-containing and sulfur-containing compound of formula (II) as claimed in claim 2 , wherein said salt of said fluorine-containing and sulfur-containing compound of formula (II) is a salt of potassium.
5. The process for preparing at least one salt of a fluorine-containing and sulfur-containing compound of formula (II) as claimed in claim 3 , wherein said salt of said fluorine-containing and sulfur-containing compound of formula (II) is a salt of potassium.