1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP CAS No. 2809-21-4 Molecular Formula: C2H8O7P2 Molecular weight: 206.02. Properties: HEDP is an organophosphoric acid corrosion inhibitor. It can chelate with Fe, Cu, and Zn ions to form stable chelating compounds.It can dissolve the oxidized materials on these metalsí» surfaces. HEDP shows excellent scale and corrosion inhibition effects under temperature 250íµ. HEDP has good chemical stability under high pH value, hard to be hydrolyzed, and hard to be decomposed under ordinary light and heat conditions. Its acid/alkali and chlorine oxidation tolerance are better than that of other organophosphoric acids (salt). HEDP can react with metal ions in water system to form hexa-element chelating complex, with calcium ion in particular. Therefore, HEDPhas good antiscale and visible threshold effects. When built together with other water treatment chemicals, it shows good synergistic effects. The solid state of HEDP is crystal powder, suitable for usage in winter and freezing districts. Because of its high purity, it can be used as cleaning agent in electronic fields and as additives in daily chemicals. HEDPliquid: Normally In 250kg net Plastic Drum, IBC drum can also be used as required HEDPsolid: 25kg inner liner polyethylene (PE) bag, outer plastic woven bag, or confirmed by clients. Storage for ten months in room shady and dry place.