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Quick Details

  • Classification: Chemical Auxiliary Agent
  • CAS No.: 2809-21-4
  • Other Names: HEDP
  • MF: C2H8O7P2, C2H8O7P2
  • EINECS No.: 220-552-8
  • Purity: 98%
  • Place of Origin: Shandong, China (Mainland)
  • Type: 1-Hydroxyethylidene-1,1-diphosphonic acid
  • Usage: Coating Auxiliary Agents, Electronics Chemicals, Leather Auxiliary Agents, Paper Chemicals, Petroleum Additives, Plastic Auxiliary Agents, Rubber Auxiliary Agents, Surfactants, Textile Auxiliary Agents, Water Treatment Chemicals
  • Brand Name: Richest
  • Model Number: 6
  • Product name: 1-Hydroxyethylidene-1,1-diphosphonic acid
  • CAS: 2809-21-4
  • MW: 206.03
  • EINECS: 220-552-8
  • Melting point: 198~199℃
  • Density: 1.45

Packaging & Delivery

Packaging Details 1kg/bag 25kg/bag or based on customers' requirement.
Delivery Time 2~3 days
Product Description
Product Name: 1-Hydroxyethylidene-1,1-diphosphonic acid

CAS: 2809-21-4
MF: C2H8O7P2
MW: 206.03
EINECS: 220-552-8

Melting point:198~199℃
Density:  1.45 (60% aq.)
Merck :14,3863                               
Stability: Stable. Incompatible with strong oxidizing agents.

Specifications Items
Colorless to pale yellow transparent liquid
White powder solids
Active content (as HEDP), %
50.0 min
60.0 min
90.0 min
pH (1% solution)     
Calcium chelating value, mg/g  
450 min
500 min
800 min
Phosphorous acid (as PO33-), % 
2.0 max
2.0 max
0.80 max
Clear, Colorless to pale yellow aqueous solution
White crystal powder
Active content (HEDP)%
60.0 min
90.0 min
Active content (HEDP·H2O)%
98.0 min
Phosphorous acid (as PO33-)%
1.0 max
0.8 max
Phosphoric acid (as PO43- )%
0.6 max
0.5 max
Chloride (as Cl-)%
0.01 max
0.01 max
pH (1% water solution)
2.0 max
2.0 max
Fe, mg/L
10.0 max
5.0 max
Colour APHA (Hazen)
10.0 max



 Etidronate (Didronel) is a human protein tyrosine phosphatase inhibitor with IC50 of 0.2 μM.

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

HEDP solid: 25kg/bag,customers’ requirement.

Storage for ten months in room shady and dry place.

Packing & Delivery
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* View our Factory.

After-Sales Service

* Training how to instal the machine, training how to use the machine. 

* Engineers available to service machinery overseas.

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China (Mainland) | Trading Company
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75 Transactions 50,000+
The supplier’s transactions conduted via Alibaba.com in the past 6 months.
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Supplier's Trade Assurance Limit: US $33,000
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