HEDP Cas No: 2809-21-4 is an organic phosphoric acid corrosion inhibitor. It can chelate with iron, copper and zinc ions to form stable chelating compounds, and can dissolve oxidized substances on the surface of these metals. HEDP Cas No: 2809-21-4 has excellent scale and corrosion inhibition performance at a temperature of 250°C. HEDP has good chemical stability at high pH, and is not easily hydrolyzed or decomposed under normal light and heating conditions. Its acid/alkali and chlorine oxidation resistance are better than other organic phosphoric acid (salt). HEDP Cas No: 2809-21-4 can react with metal ions in the water system to form a six-element chelate, especially with calcium ions. Therefore, HEDP has good fouling resistance and visible threshold effect. When used with other water treatment chemicals, it shows good synergy. ZXCHEM GROUP