Disodium ethylenediaminetetraacetate

Disodium ethylenediaminetetraacetate, also known as EDTA-2Na, is an excellent chelating agent in chemistry. Its chemical formula is C10H14N2Na2O8, with a molecular weight of 336.206. It has six coordinating atoms, and the complexes it forms are called chelates. EDTA is commonly used in complexometric titrations, typically to determine the content of metal ions. EDTA has important applications in industries such as dyes, food, and pharmaceuticals.

Disodium ethylenediaminetetraacetate is a white or milky crystalline or granular powder that is odorless, tasteless, or slightly salty. It is soluble in water and extremely difficult to dissolve in ethanol. It is an important chelating agent that can sequester metal ions in solutions. It prevents discoloration, deterioration, and turbidity caused by metals, as well as the oxidative loss of vitamin C. It also enhances the antioxidant properties of oils (trace metals in oils, such as iron and copper, promote oil oxidation).

Among the salts of ethylenediaminetetraacetic acid, the disodium salt is the most important. It is a key complexing agent used in electroless copper plating, gold plating, lead-tin alloy plating, electrochemical polishing of steel parts, and solutions for silver plating on copper parts. EDTA-Na can also be used as a substitute. It is also employed in detergents, liquid soaps, shampoos, agricultural chemical sprays, bleaching and fixing solutions for color photographic materials, water purifiers, pH adjusters, and coagulants. In the redox initiation system for styrene-butadiene rubber polymerization, disodium EDTA serves as a component of the activator, primarily to complex ferrous ions and control the polymerization rate.