1-Hydroxy Ethylidene-1,1-Diphosphonic Acid
(HEDP)
CAS No. 2809-21-4
Molecular Formula: C2H8O7P2 Molecular weight: 206.02
Properties:
HEDP is an organophosphorus 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 values, is hard to be hydrolyzed, and hard to be decomposed under ordinary light and heat conditions. It's acid/alkali and chlorine oxidation tolerance are better than that of other organophosphorus 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.
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 a cleaning agent in electronic fields and as an additive in daily chemicals.
Specification:
Items | Index |
|
|
58.0-62.0% liquid | 60% liquid | Solid |
GB/T 26324-2010 | -- | HG/T 3537-2010 |
Appearance | Clear, Colorless to pale yellow aqueous solution | Clear, Colorless to pale yellow aqueous solution | White crystal powder |
Active content (HEDP)% | 58.0-62.0 | ≥60.0 | -- |
Phosphorous acid (as PO33-)% | 2.0 max | ≤2.0 | ≤0.8 |
Phosphoric acid(as PO43-)% | 0.8 max | ≤0.8 | ≤0.5 |
Chloride (as Cl-)% | 0.02 max | ≤0.02 | ≤0.01 |
pH (1% water solution) | 2.0 max | 1.5-2.0 | 1.5-2.0 |
Density(20℃)g/cm3 | 1.40 min | ≥1.40 | -- |
Ca sequestration (mg CaCO3/g) | 500.0 min | ≥500 | -- |
Fe, mg/L | 20.0 max | ≤20.0 | ≤10 |
Active content (HEDP·H2O)% | -- | -- | ≥97.0 |
Usage:
HEDP is used as scale and corrosion inhibition in circulating cool water systems, oil fields and low-pressure boilers in fields such as electric power, chemical industry, metallurgy, fertilizer, etc... In light weaved industry, HEDP is used as a detergent for metal and nonmetal. In the dyeing industry, HEDP is used as peroxide stabilizer and dye-fixing agent; In non-cyanide electroplating, HEDP is used as a 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.
Pure etidronic acid is white crystal, industrial etidronic acid is colorless to light yellow transparent liquid, soluble in water, methanol and ethanol. Hydroxyethylidene diphosphonic acid is a kind of chemical raw material, which is often used in industrial water treatment, household cleaning products and personal care products. This product is the main material of cyanide free electroplating. It is used to prepare cyanide free copper electroplating solution. The copper coating directly plated on sodium iron has good adhesion, smooth coating and good color. In addition, hydroxyethylidene diphosphonic acid is often used as scale and corrosion inhibitor in boiler water, circulating water and oilfield water injection treatment. It is generally combined with polyhydroxy acid scale inhibitor and dispersant, and can also be used as color fixing agent and hydrogen peroxide stabilizer in bleaching and dyeing industry.
IUPAC
(1-hydroxy-1-phosphonoethyl)phosphonic acid
SMILES
CC(O)(P(=O)(O)O)P(=O)(O)O
Shandong, China
