1-Hydroxy Ethylidene-1,1-Diphosphonic Acid
Basic Information
| Itas | Index | |
|---|---|---|
| Appearance | Clear, Colorless to pale yellow aqueous solution | White crystal powder |
| Active content (HEDP), % | 58-62 | 90.0 min |
| Active content (HEDP·H2O), % | - | 98.0 min |
| Phosphorous acid (as PO33-), % | 2.0 max | 0.8 max |
| Phosphoric acid (as PO43-), % | 0.8 max | 0.5 max |
| Chloride (as Cl-), ppm | 100.0 max | 100.0max |
| pH (1% water solution) | 2.0 max | 2.0 max |
| Density (20℃), g/cm3 | 1.43-1.47 | - |
| Fe, mg/L | 20.0 max | 10.0 max |
| Color APHA (Hazen) | 40.0 max | - |
| Ca Sequestration (mg CaCO3/g) | 500.0 min | |
Chemical Description
Hydroxyethylidene diphosphonic acid (HEDP) is a typical representative of organic phosphonic acid compounds. Due to the synergistic interaction between the stable C-P bond in its molecular structure and the hydroxyl and phosphonic acid groups, it possesses multiple core properties and is widely applied in industrial fields.
Its core attributes are prominent: first, h3 chelating and scale inhibition properties, enabling it to form stable chelates with metal ions such as calcium, magnesium, and iron. This not only reduces scale formation at the source but also disrupts the crystal structure of scale, preventing it from adhering to equipment surfaces. It achieves over 90% scale inhibition efficiency against common scales such as calcium carbonate and calcium sulfate; Second, it has high-efficiency corrosion inhibition properties, forming a dense protective film on metal surfaces such as carbon steel and copper to isolate corrosive media and reduce equipment wear. Third, it exhibits stability and solubility, raaining stable at taperatures below 200°C without decomposition, and is highly soluble in water, allowing direct use without additional solvents for convenient operation. However, HEDP has poor biodegradability, requiring proper wastewater treatment, and at high concentrations, it can irritate the skin, so protective measures must be taken during handling.
HEDP is primarily used in water treatment applications, such as industrial circulating cooling water systas, medium- and low-pressure boiler water, and oilfield injection water systas, where it can simultaneously control scale formation and corrosion, ensuring equipment efficiency and safety; In metal surface treatment, it is used for descaling and rust raoval in electroplating pretreatment to improve coating quality, and can also be used for short-term rust prevention on metals. Additionally, it can serve as a detergent additive to soften hard water and stabilize bleaching agents in the papermaking industry, helping multiple industries address production challenges.
Safety Information
Acidity, Avoid contact with eye and skin, once contacted, flush with water.