HEDP·Na, HEDP Phosphonate Sodium

Product Info:

HEDP·Na is an organic phosphonic acid corrosion inhibitor. This HEDP phosphonate can chelate with Fe, Cu, and Zn ions. HEDP sodium can dissolve the oxidized materials. It has good scale and corrosion inhibition effects even under 250°C.

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HEDP·Na has two appearance statuses. One is a colorless or yellowish transparent liquid. And the other is powder. This HEDP phosphonate is harmless. Thus, engineers use it much instead of other harmful acids.

The anti-scaling and corrosion inhibition are optimum up to 250℃. No matter at a low or high pH value. HEDP Na is not easily hydrolyzed. The Cl stability is better than that of general phosphonates.

HEDP·Na is stable under high pH value. It isn’t easy to be hydrolyzed. And also makes it hard to be decayed under light and thermal conditions. The acid/alkaline, as well as chlorine oxidation tolerance of HEDP·Na is far better than that of other natural phosphonic acids.

HEDP·Na can form six-ring chelating compounds with metal ions in a water system. Ca2+, in particular. HEDP sodium salt has great scale restraint results and noticeable dissolution threshold effects. The synergistic results are better when used with various other water treatment chemicals.

In winter, it has an additional benefit. That is, the HEDP phosphonate sodium powders do not freeze. This benefit is contrary to HEDP acidic solutions.

The HEDP·Na can quickly form stable complexes with Fe, Cu, and Zn ions. Therefore it can protect against the scale of these ions. The effect of antiscale and corrosion inhibition is best at 250℃. No matter at a low or high pH value. HEDP·Na is hard to be hydrolyzed. The Cl stability is much better than that of other phosphonates.


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


HEDP·Na is used in circulating cool water systems, medium and low-pressure boilers,  and oil field water pipelines. As the scale and corrosion inhibitor, HEDP sodium performs well in power plants, the chemical industry, metallurgy, fertilizer, etc.

In the woven industry, HEDP phosphonate sodium is used as a detergent for metal and nonmetal. And engineers use this product as a peroxide stabilizer and dye-fixing agent in the dyeing industry. You can also find this product is used as a chelating agent in non-cyanide electroplating.


  • 2-20 mg/L is preferred as a scale inhibitor.
  • 20-100 mg/L is preferred as a corrosion inhibitor
  • 1000-2000 mg/L is preferred as a cleaning agent.

Usually, HEDP Na is used together with polycarboxylic acid.

Packing and storage:

200L plastic drum, IBC(1000L), customers’ requirements.

200L plastic drum 1000L IBC

Storage for ten months in a shady room and dry place.

Safety Protection:

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


1-Hydroxyethanediphosphonic acid sodium salt, EINECS 249-559-4, (1-Hydroxyethylidene)bisphosphonic acid sodium salt, 29329-71-3, Hydroxyethylidene diphosphonic acid sodium salt, Phosphonic acid (1-hydroxyethylidene)di-sodium salt, Phosphonic acid P P’-(1-hydroxyethylidene)bis-sodium salt (1:?), Phosphonic acid (1-hydroxyethylidene)bis-sodium salt, HEDP-Na, SCHEMBL205727, LS-195483, EC 249-559-4, 329H713, Mono-sodium of 1-Hydroxy Ethylidene-1 1-Diphosphonic Acid.


  1. ChemIDplus
  2. EPA Chemicals under the TSCA
  3. European Chemicals Agency (ECHA)
  4. Hazardous Chemical Information System (HCIS), Safe Work Australia
  5. PubChem
  6. UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS)