1-Hydroxy Ethylidene-1,1-Diphosphonic Acid

Product Description

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid

(HEDP)

CAS No.: 2809-21-4 EINECS No.: 220-552-8

Molecular Formula: C₂H₈O₇P₂Molecular Weight: 206.02

RIDADR: UN 3265 8/PG III

Structural Formula:

Properties:

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid is a kind of scale and corrosion inhibitor which belongs to organic phosphonic acid. It can form stable complexes with iron, copper, zinc and other metal ions, and can also dissolve the metal surface oxide. Under 250 ℃ condition, 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid can still play a good corrosion and scale inhibition effect.

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid 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 show better than that of other organic phosphonic acid (salt) acids (salt).

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid can react with metal ions in water system to form hexa-element chelating complex, especially with calcium ions. Therefore, 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid has good anti-scale and visible threshold effects. When used in combination with other water treatment chemicals, it shows ideal synergistic effects.

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid solid state is a high purity product, suitable for cold winter areas; Because of its high purity, it is especially used as the cleaning agents in electronics industry, and additives in daily chemicals.

Applications:

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid is widely used as scale and corrosion inhibitor in industrial circulating cooling water systems of electric power, chemical industry, metallurgy, chemical fertilizer, and also in medium or low pressure boilers, oilfield water injection and oil pipeline.

Besides these applications, 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid can also be used as cleaning agent of metal and nonmetal in the textile industry, as peroxide stabilizer and fixing agent in bleaching and dyeing industry, as complexing agent in cyanide free electroplating industry, as the carrier of radioactive elements in pharmaceutical industry, and so on.

Specification:

Items	Index
Appearance	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 PO₃^3-)%	1.0 max	0.8 max
Phosphoric acid (as PO₄^3- )%	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
Density (20℃)g/cm³	1.40 min	-
Fe, mg/L	10.0 max	5.0 max
Colour APHA (Hazen)	10.0 max	-
Ca sequestration (mg CaCO₃/g)	500.0 min	-

Usage:

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:

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid Liquid: Normally in 200L HDPE drum, 1000L IBC, or customers’ requirement.

1-Hydroxy Ethylidene-1,1-Diphosphonic Acid Solid: 25kg inner liner PE bag, 1000kg woven bag, or customers’ requirement.

Storage for ten 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);