HEDP·Na2, HEDP Disodium Salt


HEDP·Na2 is an organic phosphonic acid corrosion inhibitor. It can chelate with Fe, Cu, and Zn ions. HEDP disodium salt can dissolve the oxidized materials. It has a good scale and corrosion inhibition effects even under 250℃.

This HEDP phosphonate is stable under high pH values, not easy to be hydrolyzed. It is also difficult to decompose under normal light and thermal conditions. However, its acid or alkaline and chloride oxidation tolerance are better than other organic phosphonic acids.

HEDP·Na2 can form six-ring chelating compounds with metal ions in the water system, Ca2+ in particular. HEDP disodium has good scale inhibition effects and obvious dissolution threshold effects. When used with other water treatment agents, the synergistic effects are better.

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AppearanceWhite powderColorless to yellowish transparent liquid
Active content (HEDP), %74.0~79.016.5 Min.
Active content (HEDP Na2), %89.8 Min.20.0 Min.
pH (1% water solution)4.0~6.04.0~6.0
density (20℃), g/cm31.12-1.22
Phosphorous acid (PO33-), %3 Max.
Fe, mg/L35 Max.
Moisture, %3.0-6.0


HEDP·Na2 is widely used as a scale and corrosion inhibitor in circulating cool water systems, medium and low-pressure boilers, and oil field water pipelines. Other fields include electric power, the chemical industry, metallurgy, fertilizer, etc. HEDP disodium salt also has excellent performance.

In the woven industry, HEDP·Na2 is used as a detergent for metal and nonmetal. In the dyeing industry, HEDP disodium is used as a peroxide stabilizer and dye-fixing agent. In non-cyanide electroplating, HEDP·Na2 is used as a chelating agent.

Packing and storage:

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

200L plastic drum 1000L IBC

Solid: 25 kg bag, customers’ requirements. Storage for ten months in a shady room and dry place.

weaved plastic bag

Safety Protection:

Weak acidity. Avoid contact with eyes and skin. Once contacted, flush with water.