1-Hydroxy Ethylidene-1,1-Diphosphonic Acid(HEDP)
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1-Hydroxy Ethylidene-1,1-Diphosphonic Acid(HEDP)

Item No.: CAS NO.2809-21-4 
HEDP (dequest 2010)  is mainly used as a Scale & Corrosion Inhibitor, chelating (Sequestrating), deflocculating agent in Cooling and Boiler water treatment, Textile Dying, Detergents etc.
Description Dangerous description
                                          1-Hydroxy Ethylidene-1,1-Diphosphonic Acid ,HEDP 

1. Product name: 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid , Deuest 2010 Abbr:  HEDP,HEDP(A);HEDPA;
           Etidronic Acid;
           1-Hydroxy Ethylidene-1,1-Diphosphonic Acid;
           1-Hydroxyethylidenediphosphonic Acid;
           Hydroxyethylidene Diphosphonic acid(HEDP);
           1-Hydroxy-1,1-Ethanediyl ester;
           Oxyethylidenediphosphonic Acid(OEDP)
         Оксиэтилидендифосфоновая кислота(ОЭДФ -кислота )

2.Molecular weight: 206.02
   Molecular Formula: C2H8O7P2 
3.CAS NO.  2809-21-4 
Item Index
Appearance Clear, colorless to pale yellow aqueous solution White crystale powder
Active Content 58.0% - 62.0% 89%
Phosphorous acid (as PO33-) 2.0% max. 2.5max
Phosphoric acid (as PO43-) 0.8% max. 0.7%max
pH (1% water solution) 2.0 max. 2.0max
Chlorides(as Cl-) 100ppm max. 100ppm max
Density (20oC) g/cm3 1.34-1.40 1.447
Iron 10.0ppm max. 35ppm max
Color (APHA) 30 max.  


HEDP is widely used in the in circulating cool water system of electric power, chemical industry, metallurgy, fertilizer, etc. and widely used as a scale and corrosion inhibitor of low-pressure boilers, field waterflood, oil pipeline.In light&textile industry, HEDP is used as detergent for metal. 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.
6.package and Storage: Packed  250kg/drum or 1300kg/ibc 

UN NO.:3265    Class: 8

Dangerour Mark:

Security ID:S26 S39

Hazard Identification:R41 R37/38