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 also 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 status. One is a colorless or yellowish transparent liquid. And the other is powder. This HEDP phosphonate is harmless. Thus, engineers like to use it much instead to use other harmful acids.

The anti-scaling and corrosion inhibition are optimum up to 250°C. No matter at 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 is difficult to be hydrolyzed. And also it hard to be decayed under the light as well as thermal condition. 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. When it is used with various other water treatment chemicals, the synergistic results are better.

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, Zn ions. Therefore it can protect against the scale of these ions. The effect of antiscale and corrosion inhibition is best at 250°C. No matter at 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 system, medium, and low-pressure boiler,  and oil field water pipelines. As the scale and corrosion inhibitor, HEDP sodium has a good performance in fields. Such as power plant, chemical industry, metallurgy, fertilizer, etc..

In the woven industry, HEDP phosphonate sodium is used as detergent for metal and nonmetal. And engineers use this product as a peroxide stabilizer and dye-fixing agent in dyeing industry. Additionally, 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 the 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 eye 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


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  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)