... -1,1-Diphosphonic Acid Dequest 2014 Molecular Formula: C2H8-xO7P2Kx (HEDP Kx)Potassium salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid ... 2010, HEDP·Kx has better dissolution ability than that of sodium salt under neutral condition. HEDP·Kx is a good scale ... , it can be used in metal corrosion inhibitor, antifouling agent of swimming pool, metal cleaning, volume cleaning, iron dust controlling, ...