1-Hydroxy Ethylidene-1,1-Diphosphonic Acid / HEDP
CAS No. 2809-21-4
EINECS: 220-552-8
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 temperatures of 250°C. HEDP has good chemical stability under high pH values, is hard to hydrolyze, and is hard to decompose under ordinary light and heat conditions. Its acid/alkali and chlo rine oxidation tolerance are better than that of other organophosphoric acids (salt). HEDP can react with metal ions in the water system to form a hexa-element chelating complex, with calcium ions in particular. Therefore, HEDP has good antiscale and visible threshold effects. When built together with other water treatment chemicals, it shows good synergistic effects.
Application:
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
Item | Specification |
Appearance | WHITE CRYSTAL POWDER |
PH | ≤2.0 |
Active Content (%) | ≥90.0% |
ACTIVE CONTENT (as HEDP.H2O) % | ≥98.0% |
Iron (As Fe), ppm | 10ppm max |
Chloride (Aa Cl-),% | 0.05 max |
Chloride | ≤100 ppm |
Fe | ≤10 ppm |
25 kg bag, 25 mt / 20GP



Sinobio is a group company who has 2 production sites in China: One is in Jiangxi province which produce fungicide such as lsothiazolinon,BIT,Zinc Pyrithione ,etc.Our products can be widely used in the fields of oil-field water injection, pulp and paper making,water treatment,marine paint, wood, plastic leather,paint coating,cosmetics,personal care products, textiles, fiber, building materials,etc. for sterilization,corrosion prevention and mildew prevention.In particular, it has been widely recognized in the application of sterilization,algae killing,scale inhibition and corrosion inhibition of circulating cooling water in petrochemical, power metallurgy and other industrial fields.
The other one was located in Gansu province which produce water treatment chemicals such as ATMP, HEDP,THPS,TXP etc .Our company has realized the research and development, production and sales of products and provided a series of services such as water treatment engineering solutions. The products are widely used in electric power,chemical industry, metallurgy, textile,paper making, washing, building mate- rials and other fields.
All these products are exported to Europe,America,Southeast Asia and other parts of the world, and have won the praise of custom.
SINOBIO Warmly welcome customers from at home and abroad to cooperate with us for common success.

1. Can I get samples ?
Yes, we can supply specified quantity free sample, you pay for the freight charge only.
2. Which documents do you support?
Normally speaking, our MOQ is 1 standard package. But we can supply free sample for testing before mass order.
4. How can you guarantee the quality of your products?
(2) Free sample or pre- shipment sample are available for our new cooperation before you place commercial order.
We are sure the same specification commercial products as sample to customers.
(3) Third Party Inspection like SGS can be arranged according to your requirement before shipping.
(4) On-Spot QC in our APPROVED associated production bases with necessary certification like GMP, ISO etc.