Tetra Sodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•Na4 Granule) is the tetrasodium salt of HEDP, typically supplied as a white granular solid. It is an effective scale inhibitor and chelating agent widely used in industrial water treatment, cleaning products, and other applications.
Key Properties and Specifications
The granular form is designed for ease of handling, with good flow properties, low dust content, and low hygroscopicity, making it convenient for use in various conditions, including winter.
Property Specification (Typical)
Molecular Formula C₂H₄O₇P₂Na₄
Molecular Weight 294
CAS Number 3794-83-0
Appearance White granule
Active Content (as HEDP·Na₄) 81.0% – 90.0%
Active Content (as HEDP) 57.0% – 63.0%
pH (1% solution) 11.0 – 12.0 (Alkaline)
Bulk Density (20°C) 0.70 – 1.10 g/cm³
Main Applications and Functions
HEDP•Na4 performs several key functions across different industries:
Scale and Corrosion Inhibition: As an organic phosphonate, it is an excellent inhibitor for calcium carbonate scale. It can form stable complexes with metal ions like Fe, Cu, and Zn, helping to dissolve metal surface oxides and providing good scale and corrosion inhibition even at temperatures up to 250°C. It is widely used in circulating cooling water systems, low-pressure boilers, and oilfield water pipelines.
Chelating Agent: It is a powerful chelating agent that stabilizes metal ions in water, which enhances detergency in household and industrial cleaning agents, particularly under high-pH washing conditions.
Other Industrial Uses: It serves as an oxygen bleaching stabilizer in dyeing and paper industries, a corrosion inhibitor in swimming pools, and an additive in cosmetics and personal care products to prevent rancidity and discoloration.
Usage and Safety
Dosage: When used as a chelating agent in cleaning, the typical dosage is around 1-5%. It can be used effectively with other agents like polyacrylate sodium for improved performance.
Safety: HEDP•Na4 is alkaline. Avoid contact with eyes and skin. In case of contact, flush immediately with plenty of water and seek medical advice if needed.HEDP•Na4 Granule is a convenient, high-performance form of HEDP’s sodium salt. Its combination of excellent scale inhibition, metal chelation, and good handling properties makes it a valuable chemical for water treatment, cleaning, and other industrial applications.