【CAS】 2809-21-4
Alias: 1-Hydroxy Ethidene -1, 1-Diphosphonic Acid Dequest: 2010
Molecular Formula: C2H8O7P2 Molecular weight: 206. 02
1, Properties
HEDP is an organophosphoric acid corrosion inhibitor. It can chelate with Fe, Cu, and Zn etc. metal ions and form stable complex compound. It can dissolve the oxidized materials on these metals’ surfaces. Under 250℃ HEDP shows excellent scale and corrosion inhibition ability. 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 of HEDP is high purity product, suitable for using in winter and freezing districts. it is quite suitable for using as cleaning agent in electronic fields and as additives in daily chemicals.
2, Specification:
conform to HG/T 3537-1999
|
ITEMS |
Index | |
|
HG/T 3537-1999 |
| |
|
Appearance |
Colorless or light yellow transparent liquid |
White crystal powder |
|
Active content (as HEDP) % ≥ |
50. 0 60. 0 |
89. 0 |
|
Phosphorous acid (as PO33-)%≤ |
2. 0 2. 0 |
0. 80 |
|
Phosphoric acid (asPO43- )% ≤ |
0. 8 0. 8 |
0. 50 |
|
Chloride (as Cl-)% ≤ |
1. 0 1. 0 |
0. 10 |
|
pH (1％ solution) ≤ |
2 2 |
2. 0 |
|
Density (20℃)g/cm3 ≥ |
1. 34 1. 40 |
—— |
|
Fe ion ppm ≤ |
10 10 |
5. 0 |
|
Active content(as HEDP? H2O) % ≥ |
—— |
98. 0 |
|
Ca sequestration mg/g ≥ |
450 500 |
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