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 good scale and corrosion inhibition effects even under 250°C.

This HEDP phosphonate is stable under high pH value, not easy to be hydrolyzed. It is also not easy to be decomposed under normal light and thermal condition, its acid/alkaline and chloride oxidation tolerance are better than that of 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 in circulating cool water system, medium and low-pressure boiler, oil field water pipelines as scale and corrosion inhibitor. In other fields such as electric power, 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 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 eye and skin. Once contacted, flush with water.