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Tetra Sodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP意a4 Granule

Synonyms: Tetrasodium etidronate

CAS No.: 3794-83-0                                                  EINECS No.: 223-267-7

Molecular Formula: C2H4O7P2Na4                       Molecular weight: 294

Structural Formula:

Tetra Sodium Salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•Na4)

Properties and Usage:

HEDP•Na4 is even granule with excellent fluidity, low dust content, low hygroscopicity and easy handling properties.

HEDP•Na4 is a powerful chelating agent. As a household cleaning agent and industrial cleaner auxiliary, HEDP意a4 can stabilize metal ions in water and enhance effect of decontamination under high pH washing condition.

HEDP•Na4 can be used in cosmetics and personal care to restrain rancidity and discoloration.

HEDP•Na4 can be used as slow-release scale corrosion inhibitor after being compressed into tablets with other auxiliaries. HEDP•Na4 works as oxygen bleaching stabilizer in dyeing and paper making industry.


Items Index
Appearance White granule
Active content (HEDP), % 57.0-63.0
Active content (HEDP意a4), % 81.0-90.0
Moisture, % 10.0 max
Particle Size Distribution(<250μm), % 4.0 max
Particle Size Distribution(>800μm), % 5.0 max
Bulk density(20℃), g/cm3 0.70-1.10
PH (1% water solution) 11.0-12.0
Fe, mg/L 20.0 max


The dosage of HEDP•Na4 is around 1.0-5.0% when used as chelating agent in cleaning industry. It works better when combined with polyacrylate sodium, copolymer of maleic and acrylic acid.

Package and Storage:

The packing of HEDP•Na4 granule is film lined kraft valve bag, with net weight 25kg/ bag, 1000kg/ tonnage bag, or as per customer’s request. Storage for one year in shady room and dry place.

Safety Protection:

HEDP意a4 is alkaline, pay attention to labor protection during operation. Avoid contacting with eye and skin, once contacted, flush with water and then seek medical advice.

Related Products:   Tetra sodium of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP•Na4
                                     Potassium salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP•Kx
                                     1-Hydroxy Ethylidene-1,1-Diphosphonic Acid HEDP