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Tetra Sodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP.Na4)

CAS No. 3794-83-0 EINECE NO. 223-267-7
Molecular Formula C2H4O7P2Na4 Molecular Weight 294
Structural Formula

HEDP.Na4 Structural Formula

Product Features

HEDP.Na4 is the tera sodium salt of HEDP (Tetrasodium (1-hydroxyethylidene) biphosphonate). HEDP.Na4 has excellent scale inhibition for calcium carbonate (CaCO3) and chlorine stability.

HEDP•Na4 solid form soluble in water, easily deliquescence, suitable for use in winter and freezing districts. It is a kind of organophorphonic acid scale and corrosion inhibitor, can form stable complex with Fe, Cu and Zn ions. HEDP.Na4 solid can dissolve the oxides on metal surface, it has good scale and corrosion inhibition effect under 250℃.

Technical Specification

Parameter Standard
Liquid Solid
Appearance Colorless to light yellow transparent liquid White powder
Active component(HEDP), % 20.3-21.7 56.0 min 60.0 min
Active content (HEDP•Na4), % 29.0-31.0 80.0 min 85.0 min
Fe, mg/L 20.0 max 35.0 max 35.0 max
Moisture, % -- 15.0 max 10.0 max
Density (20℃), g/cm3 1.26-1.36 -- --
pH (1% water solution) 10.0-12.0 10.0-12.0 10.0-12.0

Applications & Usage

HEDP•Na4 is widely used as scale and corrosion inhibitor in circulating water system, medium and low pressure boiler, oil field water pipelines,Household and I&I (industrial & institutional) cleaners, detergents.

In light woven industry, HEDP.Na4 is used as detergent for metal and nonmetal.

In dyeing industry, HEDP.Na4 is used as peroxide stabilizer and dye-fixing agent;

In non-cyanide electroplating, HEDP.Na4 is used as chelating agent.

Scale and Corrosion inhibition Performance

CaCO3 inhibition CaSO4 inhibition Ca3(PO4)2 inhibition BaSO4 inhibition CaF2 inhibition
Excellent Poor Very Good Good Good
Calcium Tolerance Iron Control Sequestration Steel corrosion inhibition
Poor Yes Good Very Good

Package & Storage

HEDP.Na4 Solid HEDP.Na4 Liquid
25kg Bag Bulk Bag 25L Drum 200L Drum 1000L IBC ISO Tank
Once contacted with eye and skin, flush with plenty of clean water.

Hazard & Safety Precaution

Hazard Information Safety Precaution

Not regulated

Once contacted with eye and skin, flush with plenty of clean water

Alternative Name / Synonyms

  1. Disodium Etidronate Hydrate;
  2. Disodium dihydrogen bisphosphonate (1-hydroxyethylidene)bisphosphonate

HEDP.Na4 related products :

  1. Disodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid
  2. 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP)
  3. Disodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•Na2)
  4. Potassium salt of 1-HydroxyEthylidene-1,1-Diphosphonic Acid (HEDP•Kx)