Specification :

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP)
CAS No. 2809-21-4 Dequest:2010
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 metals’ surfaces. HEDP shows excellent scale and corrosion inhibition effects under temperature 250. 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.

Specification:
Appearance Colorless or light yellow transparent liquid White crystal powder
Active content (HEDP)% 58.0-62.0 89.0 min
Phosphorous acid (as PO33-)% 2.0 max 0.5 max
Phosphoric acid (asPO43- )% 0.8 max 0.5 max
Chloride (as Cl-)% 0.01 max 0.01 max
pH (1 solution) 2 max 2 max
Density (20)g/cm3 1.40 -
Fe ion ppm 10 max 20 max
Colour APHA (Hazen) 40 max -
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