1-Hydroxy Ethylidene-1,1-Diphosphonic Acid
(HEDP)

CAS No. 2809-21-4

Molecular Formula: C2H8O7P2 Molecular weight: 206.02

Structural Formula:




Specification:
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-):100.0ppm max
pH (1% solution): 2.0 max
Density (20℃):1.43-1.47g/cm3
Fe，mg/L: 10.0 max
Colour APHA (Hazen): 30.0 max
Ca sequestration (mg CaCO3/g): 500.0 min

Usage:HEDP is used as scale and corrosion inhibition in circulating cool water system, oil field and low-pressure boilers in fields such as electric power, chemical industry, metallurgy, fertilizer, etc.. In light woven 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.