Water Treatment Chemicals, Phosphonates, Polymers, Biocides

Organophosphoric Antiscale and Corrosion Inhibitors, Chelant

Monosodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•Na)

CAS No.: 29329-71-3

Molecular Formula: C2H7O7P2Na

Molecular weight: 228

Structural Formula:

Monosodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•Na)


HEDP•Na is an organophosphonic acid corrosion inhibitor, it can chelate with fe, cu, and zn ions. HEDP•Na can dissolve the oxidized materials, it has good scale and corrosion inhibition effects even under 250℃, it is stable under high pH value, not easy to be hydrolyzed, not easy to be decomposed under normal light and heat condition, its acid/alkaline and chloride oxidation tolerance are better than that of other organophosphonic acids. HEDP•Na can form six-ring chelating compounds with metal ions in water system, ca2+ in particular. HEDP•Na has good scale inhibition effects and obvious dissolution threshold effects. When used with other water treatment agents, the synergistic effects is better.

HEDP•Na is suitable for acidic scale inhibitor and detergent, can be used for metal surface treatment.


items index
Appearance Colorless or yellowish transparent liquid
Active content (HEDP)% 19.0-21.0
Fe,mg/L 20 max
PH (1% water solution) 2.3-2.9
Density (20℃) g/cm3 1.11-1.21


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

When used as scale inhibitor, the dosage 2-20mg/l is preferred, when used as corrosion inhibitor, the dosage 20-100mg/l is preferred, when used as cleaning agent, the dosage 1000-2000mg/l is preferred. Usually, HEDP•Na is used together with polycarboxylic acid.

Package and Storage:

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

Safety Protection:

Acidity, Avoid contact with eye and skin, once contacted, flush with water. 


Shandong IRO Water Treatment Co., Ltd.

Office Address: 2802, 1st Building, No.19 Zhangzhou 2nd Rd, Qingdao, China
Factory Address: Qicun Town, Shizhong, Zaozhuang, Shandong, China
Tel: +86-532-85027466 Fax: +86 532 85028486
Email: info@irowater.com

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