CAS No. 2809-21-4
Molecular Formula: C2H8O7P2
Molecular weight: 206.02
Structural Formula:
Properties:
Hydroxyethylidene Diphosphonic acid(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.
Hydroxyethylidene Diphosphonic acid(HEDP)
shows excellent scale and corrosion inhibition effects under
temperature 250℃.
Hydroxyethylidene Diphosphonic acid(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).
Hydroxyethylidene Diphosphonic acid(HEDP)
can react with metal ions in water system to form
hexa-element chelating complex, with calcium ion in
particular. Therefore,
Hydroxyethylidene Diphosphonic acid(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
Hydroxyethylidene Diphosphonic acid(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:
Hydroxyethylidene Diphosphonic acid(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,
Hydroxyethylidene Diphosphonic acid(HEDP)
is used as
detergent for metal and nonmetal. In dyeing industry,
Hydroxyethylidene Diphosphonic acid(HEDP) is used as
peroxide stabilizer and dye-fixing agent; In non-cyanide
electroplating,
Hydroxyethylidene Diphosphonic acid(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,
Hydroxyethylidene Diphosphonic acid(HEDP)
is used together with
polycarboxylic acid.
Package and Storage:
Hydroxyethylidene Diphosphonic acid(HEDP)
liquid:HEDP liquid: 200L plastic drum,IBC(1000L),customers’ requirement.
Hydroxyethylidene Diphosphonic acid(HEDP)
solid: 25kg/bag,customers’ requirement.
Storage for twelve months in shady room 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)
