Tetrasodium EDTA explained

Tetrasodium EDTA is the salt resulting from the neutralization of ethylenediaminetetraacetic acid with four equivalents of sodium hydroxide (or an equivalent sodium base). It is a white solid that is highly soluble in water. Commercial samples are often hydrated, 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 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.

thumb|left|Ethylenediaminetetraacetic acid is the acidic form of tetrasodium EDTA.

Products

See also: Ethylenediaminetetraacetic acid. The substance is also known as Dissolvine E-39. It is a salt of edetic acid. It has been known at least since 1954.^{[1] [2]} It is sometimes used as a chelating agent.^{[3] [4] [5]}

The assignee on 5% of patents at the USPTO containing the substance is the firm Procter and Gamble. 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, and scale from ferrous metal, copper, brass, and other surfaces.^[6]

At a concentration of 6%, it is the main active ingredient in some types of engine coolant system flushes.^[7]

Notes and References

1. News: Tetrasodium ethylenediaminetetraacetate . 3 April 2021 . European Chemicals Agency.
2. T. T. Trujillo . H. Foreman . The metabolism of C14 labeled ethylenediaminetetraacetic acid in human beings . The Journal of Laboratory and Clinical Medicine . 1954. 43 . 4 . 566–571 . 13163555 .
3. Alessandro Fulgenzi . Maria Elena Ferrero . EDTA Chelation Therapy for the Treatment of Neurotoxicity. International Journal of Molecular Sciences . February 2019 . 20 . 5 . 1019 . 10.3390/ijms20051019 . free . 30813622 . 6429616.
4. Swaran J.S. Flora . Vidhu Pachauri . Chelation in Metal Intoxication . International Journal of Environmental Research and Public Health . June 2010 . 7 . 7 . 2745–2788 . 10.3390/ijerph7072745 . 20717537 . 2922724. free .
5. 10.1021/jp963102d. Chelating Behavior between Metal Ions and EDTA in Sol−Gel Matrix. 1997. Zaitoun. Mohammed A.. Lin. C. T.. The Journal of Physical Chemistry B. 101. 10. 1857–1860.
6. News: Thomas . Glenn C. Sr. . Rust, corrosion, and scale remover . US5468303A . United States Patent and Trademark Office . 1995-11-21.
7. Web site: SAFETY DATA SHEET. Fcsdchemicalsandlubricants.com. 14 March 2022.