METHOD OF PRODUCING TRIFLUOROMETHANESULPHINIC ACID Russian patent published in 2013 - IPC C07C313/04 

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing trifluoromethanesulphinic acid of high purity from an aqueous mixture containing a salt of trifluoromethanesulphinic acid, a salt of trifluoroacetic acid and salt impurities formed from a method for production thereof, where said mixture is subjected to the following operations: acidification in order to separate salts of trifluoroacetic acid and triflic acid in form of an acid, using a strong acid having pKa value less than or equal to 1; separating trifluoroacetic and trifluoromethanesulphinic acid by distillation with extraction of trifluoroacetic acid from the overhead distillate, and trifluoromethanesulphinic acid together with excess strong acid, salts of strong acids, particularly salts formed as a result of acidification, and water from the bottom part of the distillation column; separating by distillation of the trifluoromethanesulphinic present in the still residue of distillation obtained before that.

EFFECT: obtaining trifluoromethanesulphinic acid of high purity from an aqueous mixture containing a salt of trifluoromethanesulphinic acid.

19 cl, 4 ex