Etidronate disodium

Etidronate disodium (CAS 7414-83-7), also known as HEDP disodium, is the disodium salt form of hydroxyethylidene diphosphonic acid used commercially as a chelating and sequestering agent.

Where is Etidronate disodium used?

• Water treatment: controls calcium carbonate and metal oxide scale in cooling towers, boilers, and process water systems
• Personal care: incorporated into shampoos and creams; sequesters trace metals in rinse-off products to prevent destabilisation of peroxide-based systems or rancidity
• Textile and leather processing: deactivates hardness ions, improving process consistency and colour yield in dye baths and bleaching liquors
• Pharmaceutical manufacturing: stabilising excipient in liquid formulations where oxidation must be controlled
• It binds metal ions, particularly calcium and heavy metals, to prevent scale formation, oxidative degradation, and microbial activity.

Good to know: Material is available to meet USP and BP standards, with food-contact and cosmetic-grade material available to meet purity requirements for various regulated applications.

Commercial specifications

• Solution concentrations typically around 30–40%