Tetrasodium EDTA is the salt resulting from the neutralization of

ethylenediaminetetraacetic acid Ethylenediaminetetraacetic acid (EDTA) is an aminopolycarboxylic acid with the formula H2N(CH2CO2H)2sub>2. This white, water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes eve ...

with four equivalents of

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali ...

(or an equivalent sodium base). It is a white solid that is highly soluble in water. Commercial samples are often

hydrated Drinking is the act of ingesting water or other liquids into the body through the mouth, proboscis, or elsewhere. Humans drink by swallowing, completed by peristalsis in the esophagus. The physiological processes of drinking vary widely among ot ...

, e.g. Na₄EDTA^.4H₂O. The properties of solutions produced from the anhydrous and hydrated forms are the same, provided they are at the same pH. It is used as a source of the

chelating agent Chelation is a type of bonding of ions and molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These ligands are ...

EDTA^4-. A 1% aqueous solution has a pH of approximately 11.3. When dissolved in neutral water, it converts partially to H₂EDTA^2-. Ethylenediaminetetraacetic acid is produced commercially via the intermediacy of tetrasodium EDTA. left, Ethylenediaminetetraacetic acid is the acidic form of tetrasodium EDTA.

Products

The substance is also known as Dissolvine E-39. It is a salt of

edetic acid Ethylenediaminetetraacetic acid (EDTA) is an aminopolycarboxylic acid with the formula H2N(CH2CO2H)2sub>2. This white, water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-soluble complexes eve ...

. It has been known at least since 1954. It is sometimes used as a

. The assignee on 5% of patents at the

USPTO The United States Patent and Trademark Office (USPTO) is an agency in the U.S. Department of Commerce that serves as the national patent office and trademark registration authority for the United States. The USPTO's headquarters are in Alexa ...

containing the substance is the firm

Procter and Gamble The Procter & Gamble Company (P&G) is an American multinational Final good, consumer goods corporation headquartered in Cincinnati, Cincinnati, Ohio, founded in 1837 by William Procter (industrialist), William Procter and James Gamble (industr ...

. It is used most notably in cosmetics and hair and skin care products. The substance has been used to aid in formulation of a removal product for rust,

corrosion Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engine ...

, and scale from

ferrous metal In chemistry, the adjective Ferrous indicates a compound that contains iron(II), meaning iron in its +2 oxidation state, possibly as the divalent cation Fe2+. It is opposed to "ferric" or iron(III), meaning iron in its +3 oxidation state, such ...

copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...

brass Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other with ...

, and other surfaces. At a concentration of 6%, it is the main active ingredient in some types of engine coolant system flushes.

References

{{Consumer Food Safety Acetic acids Amines Antidotes Chelating agents Preservatives E-number additives