HEDP Na, Hydroxyethylidene Diphosphonic Monosodium


HEDP·Na is the monosodium of hydroxy ethylidene diphosphonic acid. It is an organophosphorus acid corrosion inhibitor. This HEDP monosodium salt can chelate with Fe, Cu, and Zn ions. As a result, it can dissolve the oxidized materials.

HEDP·Na has good scale and corrosion inhibition effects even under 250℃. It is stable under a high pH value. HEDP·Na is not easy to be hydrolyzed and decompose under normal light and heat conditions. Its acid/alkaline and chloride oxidation tolerance are better than other organophosphonic acids.

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HEDP·Na structure formula


AppearanceColorless or yellowish transparent liquid
Active content (HEDP), %19.0-21.0
pH (1% water solution)2.3-2.9
Density (20℃), g/cm31.11-1.21
Fe, mg/L20 Max.


HEDP·Na can form six-ring chelating compounds with metal ions in water systems, Ca2+ in particular. This hydroxy ethylidene diphosphonic has good scale inhibition and obvious dissolution threshold effects. In addition, when used with other water treatment agents, the synergistic effects are better.

HEDP·Na is suitable for acidic scale inhibitors and detergents. It also can be used for metal surface treatment.

HEDP·Na is used in circulating cool water systems, medium and low-pressure boilers, and oil field water pipelines as a scale and corrosion inhibitor in fields such as power plants, the chemical industry, metallurgy, fertilizer, etc. In the light woven industry, this product is used as a detergent for metal and nonmetal. In the dyeing industry, this product is used as a peroxide s|tabilizer and dye-fixing agent; In non-cyanide electroplating, this product is used as a chelating agent.


When used as a scale inhibitor, 2~20 mg/L is preferred. When used as a corrosion inhibitor, 20~100 mg/L is preferred. The dosage of 1000~2000 mg/L is preferred when used as a cleaning agent. Usually, HEDP·Na is used together with polycarboxylic acid.

Packing and Storage:

200L plastic drum, IBC(1000L), customers’ requirement. Storage for ten months in a shady room and dry place.

200l plastic drum 1000l IBC

Safety Protection:

Acidity, avoid contact with the eyes and the skin. Once contacted, flush with water.


(1-hydroxyethylidene)bisphosphonic acid sodium salt, Sodium Etidronate.


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