1-Hydroxyethylidene-1,1-diphosphonic Acid (HEDP) HEDP Molecular Formula: C2H8O7P2 Molecular Weight: 206.03 CAS: 2809-21-4 EINECS: 220-552-8 Property: HEDP is an organophosphoric acid corrosion inhibitor. It can chelate with Fe, Cu, and Zn etc. metal ions and form stable complex compound. It can dissolve the oxidized materials on these metals’ surfaces. Under 250℃ HEDP shows excellent scale and corrosion inhibition ability. 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, HEDP has good antiscale and visible threshold effects. When built together with other water treatment chemicals, it shows good synergistic effects. Application: HEDP is widely used in the in circulating cool water system of electric power, chemical industry, metallurgy, fertilizer, etc. and widely used as a scale and corrosion inhibitor of low-pressure boilers, field waterflood, oil pipeline. In light&textile industry, HEDP is used as detergent for metal and nonmetal. In dyeing industry, HEDP is used as peroxide stabilizer and dye-fixing agent; In non-cyanide electroplating, HEDP is used as chelating agent. The dosage of 1-10mg/L is preferred as scale inhibitor, 10-50mg/L as corrosion inhibitor, and 1000-2000mg/L as detergent. Usually, HEDP is used together with polycarboxylic acid. Packing: liquid: Normally In 30kg or 250kg net Plastic Drum; solid: 25kg inner liner polyethylene (PE) bag, outer plastic woven bag Specification: items index Appearance Clear, Colorless to pale yellow aqueous solution White crystal powder Active content (HEDP)% 58.0-62.0 90.0 min Active content (HEDP·H2O)% - 98.0 min Phosphorous acid (as PO33-)% 1.0 max 0.8 max Phosphoric acid? (asPO43-?)% 0.6 max 0.5 max Chloride (as Cl-) ppm 100.0 max 50.0max pH (1% solution) 2.0 max 2.0 max Density? (20℃)g/cm3 1.43-1.47 - Fe，mg/L 10.0 max 5.0 max Colour APHA (Hazen) 30.0 max - Acetic acid % 0.5 max ? Ca sequestration (mg CaCO3/g) 500.0 min ?
HEDP is widely used in the in circulating cool water system of electric power, chemical industry, metallurgy, fertilizer, etc. and widely used as a scale and corrosion inhibitor of low-pressure boilers, field waterflood, oil pipeline. In light&textile ind

CAS NO:2809-21-4

EC NO:220-552-8

Molecular Formula:C₂H₈O₇P₂

Molecular Weight:201.9987

Synonyms:;1-Hydroxyethane-1,1-diphosphonic Acid;Etidronic acid;HEDP;HEDPA; Hydroxy Ethylidene-1,1-Diphosphonic Acid;1-Hydroxy Ethylidene-1,1-Diphosphonic Acid;1-Hydroxyethylidene diphosphonic Acid;1-hydroxy ethylene-1,1-diphosphonic acid;1-HYDROXYETHYLIDENEDI(PHOSPHONIC ACID);disodium (1-hydroxyethane-1,1-diyl)bis[hydrogen(phosphonate)];(1-hydroxyethane-1,1-diyl)bis(phosphonate);Hydroxyethylidenedi(phosphonic acid);Hydroxyethylidine Diphosphonic Acid;HydroxyEthylidene Diphosphonic acid;

Molecular Structure: