Sodium Salt of 1-Hydroxyethylene -1, 1,-Diphosphonic Acid
(Passed REACH Pre-registration)
CAS Number: 3794-83-0(4-Na), 29329-71-3(x-Na)
Molecular Formula: C2H4O7P2 Na4
Molecular Weight: 294
HEDP.4Na is the sodium salt of HEDP, it is an good scale inhibitor for calcium carbonate, it can be used in low pressure boiler water system, circulating water system, industrial and municipal cleaning water system and swimming pool.
The solid HEDP.4Na is white powder, soluble in water, easily deliquescence, suitable for use in winter and freezing districts. It is a kind of organophorphonic acid scale and corrosion inhibitor, can form stable complex with Fe, Cu and Zn ions, it can dissolve the oxides on metal surface, it has good scale and corrosion inhibition effect under 250°C.
HEDP.4Na is widely used in circulating cool water system, medium and low pressure boiler, oil field water pipelines as scale and corrosion inhibitor in fields such as electric power, chemical industry, metallurgy, fertilizer, etc.. In light woven industry, HEDP.4Na is used as detergent for metal and nonmetal. In dyeing industry, HEDP.Na4 is used as peroxide stabilizer and dye-fixing agent; In non-cyanide electroplating, HEDP.4Na is used as chelating agent.
Water white to pale yellow liquid
White crystalline powder
Active Acid (as HEDP %)
20.3 - 21.7
57.0 - 62.0
Active Salt (as HEDP.Na4 %)
29.0 - 31.0
81.3 - 88.5
Phosphorous acid as PO33- (%)
Iron, as Fe (ppm)
Specific Gravity at 20/20°C
pH @ 25°C
10.0 - 12.0(neat solution)
11.0 - 12.0(1% water solution)
Package and Storage:
Liquid: normally in 200L HDPE drum and 1000L IBC.
Solid: 25kg inner liner polyethylene (PE) bag.
Storage for 12 months in room shady and dry place.
Weak acidity, avoid contact with eye and skin, once contacted, flush with water.