Disodium Salt of 1-Hydroxyethylidene-1, 1-Diphosphonic Acid


CAS No.: 7414-83-7
Dequest: 2016BD
Molecular Formula: C2H6O7P2Na2
Molecular Weight: 250

HEDP•Na2 is an organophosphonic acid corrosion inhibitor, it can chelate with Fe, Cu, and Zn ions, it can dissolve the oxidized materials, it has good scale and corrosion inhibition effects even at 250℃, it is stable at high pH value, not easy to hydrolyze, not easy to decompose under normal light and heat conditions, its acid/alkaline resistance and chloride oxidation resistance are better than that of other organophosphonic acids.

HEDP•Na2 can form hexatomic ring chelating compounds with metal ions in water system, Ca2+ in particular. HEDP•Na2 has a good scale inhibition effect and an obvious dissolution threshold effect. When used with other water treatment chemicals, the synergistic effect is better.

Items Index
Appearance Colorless to yellowish transparent liquid White powder
Active content ( HEDP ) % 16.5min 74.0-79.0
Active content (HEDP•Na2)% 20.0min 89.8min
density (20 ℃ )g/cm3 1.12-1.22 --
Fe3+ μ g/g -- 35max
Phosphorous acid (as PO33-)% -- 2max
Moisture % -- 3-6
PH (1% water solution) 4.0-6.0 4.0-6.0

Application scope and method of use:
HEDP•Na2 is widely used in circulating cooling water system, medium and low pressure boilers, oil field water pipelines while working as scale and corrosion inhibitor in fields such as electric power, chemical industry, metallurgy, fertilizer, etc. In light textile industry, HEDP•Na2 is used as detergent for metal and nonmetal. In dyeing industry, it serves as the fixing agent. In non-cyanide electroplating, it is used as chelating agent.

Package and Storage:
HEDP•Na2 is packed in 30kg or 250kg plastic drums, or decided by clients. Storage for ten months in shady room and in dry places.

Safety Protection:
HEDP•Na2 has a weak acidity. Avoid contact with eye and skin. In case of contact with eyes or skins, please rinse immediately with plenty of water.

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