HEDP Solid, Liquid

Short Description:

Classification: Chemical Auxiliary Agent CAS No.: 2809-21-4 MF: C2H8O7P2 Purity: ...

Product Detail

Product Tags

Chemical Auxiliary Agent
CAS No.:
Place of Origin:
China (Mainland)
Water Treatment Chemicals

Packaging & Delivery

Packaging Details
200L in plastic barrel for export, 200kg or 250kg per barrel, or confirmed by clients.
Delivery Time
15 days after the contract being signed

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid


CAS No.  2809-21-4  

Molecular Formula:   C2H8O7P2     

Molecular weight: 206.02  



HEDP is an organophosphoric acid corrosion inhibitor. It can chelate with Fe, Cu, and Zn ions to form stable chelating compounds.It can dissolve the oxidized materials on these metals’ surfaces. HEDP shows excellent scale and corrosion inhibition effects under temperature 250°C. HEDP has good chemical stability under high pH value, hard to be hydrolyzed, and hard to be decomposed under ordinary light and heat conditions. Its acid/alkali and chlorine oxidation tolerance are better than that of other organophosphoric acids (salt). HEDP can react with metal ions in water system to form hexa-element chelating complex, with calcium ion in particular. Therefore, HEDP has good antiscale and visible threshold effects. When built together with other water treatment chemicals, it shows good synergistic effects.


The solid state of HEDP is crystal powder, suitable for usage in winter and freezing districts. Because of its high purity, it can be used as cleaning agent in electronic fields and as additives in daily chemicals. 






Colorless or light yellow transparent liquid

White crystal powder

Active content (HEDP)%



Phosphorous acid (as PO33-)%

2.0 max

0.8 max

Phosphoric acid  (asPO43- )%

0.8 max

0.5 max

Chloride (as Cl-)%

1.0 max


pH (1% solution)

2 max

2 max

Density  (20°C)g/cm3




10 max

5 max

Colour APHA (Hazen)

40 max





HEDP is used as scale and corrosion inhibition in circulating cool water system, oil field and low-pressure boilers in fields such as electric power, chemical industry, metallurgy, fertilizer, etc.. In light woven industry, HEDP is used as detergent for metal and nonmetal. In dyeing industry, HEDP is used as peroxide stabilizer and dye-fixing agent; In non-cyanide electroplating, HEDP is used as chelating agent. The dosage of 1-10mg/L is preferred as scale inhibitor, 10-50mg/L as corrosion inhibitor, and 1000-2000mg/L as detergent. Usually, HEDP is used together with polycarboxylic acid.


Package and Storage:

HEDP liquid: Normally In 250kg net Plastic Drum, IBC drum can also be used as required HEDP solid: 25kg inner liner polyethylene (PE) bag, outer plastic woven bag, or confirmed by clients.

Storage for ten months in room shady and dry place.

Safety Protection:

Acidity, Avoid contact with eye and skin, once contacted, flush with water.


Related Products:  1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP

                                    Monosodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid  HEDP•Na

                                    Potassium salt of1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP•Kx

  • Previous:
  • Next:

  • Related Products

    WhatsApp Online Chat !