1-Hydroxyethylidene-1,1- Diphosphonic Acid HEDP Etidronic acid CAS 2809-21-4 is a chelating agent and may be added to bind or, to some extent, counter the effects of substances, such as calcium, iron or other metal ions, which may be discharged as a component of grey wastewater and could conceivably contaminate groundwater supplies. As a phosphonate it has corrosion inhibiting properties on unnalloyed steel. Etidronic acid also acts to retard rancidification and oxidation of fatty acids.
Appearance Clear, Colorless solution White crystal powder
Active content (HEDP)% 60.0 min 90.0 min
Active content (HEDP·H2O)% - 98.0 min
Phosphorous acid (as PO33-)% 1.0 max 0.8 max
Phosphoric acid (as PO43- )% 0.6 max 0.5 max
Chloride (as Cl-)% 0.01 max 0.01 max -
pH (1% water solution) 2.0 max 2.0 max
Density (20℃)g/cm3 1.40 min -
Fe, mg/L 10.0 max 5.0 max
Colour APHA (Hazen) 10.0 max -
Ca sequestration (mg CaCO3/g) 500.0 min -
1.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..
2.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.
3.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.
25kg bag or 250kg drum.25mt/1FCL or 20mt/1FCL
Storage & Transport
Stored in cool and airy place; away from fire and heat;handle with care;no breakage,avoid leakageThis is classified as a Common Good for transport.