Verfahren zur Rückgewinnung fluorierter Emulgatoren

摘要

Fluorinated emulsifiers, in particular, perfluorooctanoic acid are bound to anionic exchange resins for the purification of aqueous effluent from the production of fluoropolymers. Said emulsifiers may be quantitatively eluted from the exchanger with a water-miscible organic solvent, containing a small amount of ammonia. It is of advantage to distil off the ammonia containing solvent, recycle the emulsifier to a further polymerisation and recycle the ammoniacal solvent for elution. Addition of alkalis improves the elution efficiency.