Abstract A new method for recovering perfluoro-n-butanesulfonic acid from its waste alkaline salts and re-converting it into the corresponding 2, 2, 2-trifluoroethyl ester alkylating agent is described. Alkaline perfluoro-n-butanesulfonate can be converted into the corresponding acid by treating it with gaseous HCl in methanol; perfluoro-n-butanesulfonic acid is then directly esterified by treatment with 2, 2, 2-trifluoro-ethanol in thionyl chloride. Easy ...
