The extraction of chromium (iii) from aqueous edta by solutions of tetra- n-hexylammonium chloride in dichloroethane

Abstract

When a solution of chromium (III) in aqueous ethylenediaminetetraacetic acid (H 4Y) is equilibrated with a solution of the liquid anion-exchanger tetra n-hexylammonium chloride in 1,2-dichloroethane, only the violet complex CrY(H 2O) − is extracted as the ion pair NR 4 +CrY(H 2O) − (where R = n-hexyl) over the pH range 3.6–6.0. Maximal extraction occurs at pH 4.7 and the extraction constant ▪ The formally neutral species CrHY(H 2-O) and the anionic species CrY(OH) 2- and CrY(OH) 2 3- are not extractable.