Home    About us   Contact us   Products
Home About us Product Honors About REACH Contact Us 简体中文

      Place: Home  Water Treatment chemicals

 
   
  Productlist
Phosphonates Antiscalants, Corrosion Inhibitors and Chelating Agents
Salts of Phosphonates
Polycarboxylic antiscalant and dispersant
Biodegradable antiscalant and dispersant
Biocide and Algicide
Built Scale & Corrosion Inhibitors and Pretreatment Filming Agents
Corrosion Inhibitor
Oxygen Scavenger
Reverse Osmosis Chemicals
Other
   Contact Us

Shandong Taihe Chemicals Co., Ltd.
TEL:  +86-632-5113066
FAX:  +86-632-5112055
E-mail: info@thwater.net
Web: http://www.taihechem.net
          http://www.thwater.net
ADD: No.1, Shiliquan East Road, Shizhong District, Zaozhuang City, Shandong Province, P.R.China

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

CAS No.  2809-21-4

Molecular Formula:   C2H8O7P2                Molecular weight: 206.02

Structural Formula:

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

Properties:

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℃. 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. 

Specification:

Items Index
Appearance Clear, Colorless to pale yellow aqueous solution White crystal powder
Active content (HEDP)% 58.0-62.0 90.0 min
Active content (HEDP·H2O)% - 98.0 min
Phosphorous acid (as PO33-)% 2.0 max 0.8 max
Phosphoric acid  (as PO43- )% 0.8 max 0.5 max
Chloride (as Cl-)% 0.02 max 0.01 max
pH (1% water solution) 2.0 max 2.0 max
Density  (20℃)g/cm3 1.40 min -
Fe, mg/L 20.0 max 10.0 max
Ca sequestration (mg CaCO3/g) 500.0 min  

Usage:

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 twelve months in room shady and dry place.

Safety Protection:

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

Synonyms:

HEDP;HEDP(A);HEDPA;

Etidronic Acid;

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid;

Hydroxyethylidene-1,1-diphosphonicacid(HEDP);

1-Hydroxyethylidenediphosphonic Acid;

Hydroxyethylidene Diphosphonic acid(HEDP);

1-Hydroxy-1,1-Ethanediyl ester;

Oxyethylidenediphosphonic Acid(OEDP)