Hydroxyethylidene Diphosphonic Acid (HEDP)

Hydroxyethylidene Diphosphonic Acid (HEDP) is an organic phosphonic acid that acts as a powerful corrosion inhibitor and anti-scaling agent. It forms stable water-soluble complexes with metal ions such as iron, copper, and zinc, preventing them from precipitating and forming scale on equipment surfaces. HEDP is distinguished by its high thermal stability and resistance to hydrolysis, making it suitable for use in cooling water systems, boilers, and oilfield applications at high temperatures. In the detergent industry, HEDP serves as a stabilizer for peroxides and a color preservation agent. It is also used in the textile industry during bleaching processes to sequester metal ions that could damage fibers. HEDP is safer for the environment compared to traditional polyphosphates and operates effectively across a wide pH range.

Applications

Cooling water systems

Detergent stabilizer

Oilfield (scale inhibitor)

Textile bleaching