Title: Nitrilotriacetic Acid
CAS Registry Number: 139-13-9
CAS Name: N,N-Bis(carboxymethyl)glycine
Synonyms: triglycollamic acid; a,a¢,a¢¢-trimethylaminetricarboxylic acid; tri(carboxymethyl)amine; triglycine; NTA
Molecular Formula: C6H9NO6
Molecular Weight: 191.14
Percent Composition: C 37.70%, H 4.75%, N 7.33%, O 50.22%
Line Formula: N(CH2COOH)3
Literature References: Prepn: Heintz,
Ann. 122, 260 (1862); Michaelis, Schubert,
J. Biol. Chem. 106, 331 (1934); Martell, Bersworth,
J. Org. Chem. 15, 46 (1950); Singer, Weisberg,
US 2855428 and
US 3061628 (1958 and 1962, both to Hampshire Chem.). IR studies: Nakamoto
et al., J. Am. Chem. Soc. 84, 2081 (1962); Chapman
et al., Proc. Chem. Soc. London 1962, 336. Solubility data: Bird,
J. Soc. Dyers Colour. 56, 473 (1940). Toxicity data:
Soap Chem. Spec. 42, 58 (1966). pK data: Schwarzenbach
et al., Helv. Chim. Acta 28, 828 (1945).
Review: Souchay, Graizon,
Bull. Soc. Chim. Fr. 1952, 34.
Properties: Prismatic crystals from hot water, mp 230-235° dec (Michaelis, Schubert). mp 241.5° (dec). 1.28 g dissolves in 1 liter of water at 22.5°, pH of satd aq soln is 2.3 (Bird). At 20° pK 3.03, pK2 3.07, pK3 10.70.
Melting point: mp 230-235° dec (Michaelis, Schubert); mp 241.5° (dec)
pKa: pK 3.03, pK2 3.07, pK3 10.70
Derivative Type: Sodium salt
Synonyms: NTANa3
Trademarks: Trilon A
Molecular Formula: C6H6NNa3O6
Molecular Weight: 257.08
Percent Composition: C 28.03%, H 2.35%, N 5.45%, Na 26.83%, O 37.34%
Properties: MLD orally in rats >4,000 mg/kg (
Soap Chem. Spec.).
Toxicity data: MLD orally in rats >4,000 mg/kg (
Soap Chem. Spec.)
CAUTION: Nitrilotriacetic acid is reasonably anticipated to be a human carcinogen:
Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-184.
Use: Chelating and sequestering agent; builder in synthetic detergents.