Patent ID: 8461378

Claim:
A process for the purification of fluoroalkanesulfonate salts comprising (a) contacting a mixture comprising 1) at least one fluoroalkanesulfonate salt of the formula [C(H)(F)(X)CF2SO 3 ] y M (I) wherein X is H, Cl, F, CF 3 , or OR; R is C 1 -C 6 alkyl, fluoroalkyl, or perfluoroalkyl; M is Li, Na, K, Cs, Rb, Ca, or Ba; and y is a positive integer equal to the valence of M; and 2) at least one inorganic salt contaminant, with one or more solvents to selectively dissolve at least a portion of said salt in solution; and (b) isolating the solution from the mixture to yield a fluoroalkanesulfonate salt containing less than 500 micrograms of inorganic salt contaminant per gram of fluoroalkanesulfonate salt, or containing less than a maximum of 0.3% by weight of individual solvent.