A continuous ionic liquid extraction process for the separation of cobalt from nickel

Abstract

A continuous ionic liquid extraction process using the ionic liquid trihexyl(tetradecyl)phosphonium chloride (Cyphos® IL 101) has been developed for the selective extraction of cobalt from nickel.The performance of this continuous extraction process is competitive with that of currently applied industrial processes. Moreover, the elimination of volatile odorous compounds from the extraction phase leads to environmentally friendlier and healthier working conditions.

Selective Extraction of Metals from Chloride Solutions with the Tetraoctylphosphonium Oleate Ionic Liquid

“…2 In this process, the metal is extracted from an aqueous phase by a hydrophobic organic extractant. However, conventional liquid-liquid extraction systems make use of organic solvents, which are often toxic and flammable.…”

Supported Ionic Liquid Membranes for Metal Separation

“…Therefore, undiluted Cyphos IL 101 can be used as both extractant and diluents when contacting with aqueous phase [53]. Undiluted Cyphos IL 101 was used for extractions of Co(II), Fe(III) and rare earths [53][54][55][56]. Extraction mechanism of metal ions with undiluted Cyphos IL101 is same as that of Cyphos IL 101 diluted in organic solvent.…”

Ionic Liquid–Liquid Chromatography: A New General Purpose Separation Methodology

“…On the preparative scale, examples (Table 5) include a complex nine-stage process [176] involving a combination of solvent extraction and electro-refining. Nickel(II) and cobalt(II) chloride have been separated by a five-stage continuous process using the ionic liquid [P 6 6 6 14 ]Cl [177]. The chromatographic separation of these metal(II) salts has been carried out using a number of techniques, including anion-exchange chromatography [178], adsorption thin layer chromatography (TLC) of metal(II) chelates [179], TLC [180], HPLC of diaminostilbene complexes [181], chromatographic separation of amino acid chelates [182], micellar electrokinetic chromatography [183], a guar-based chelating ion exchange resin chromatography [184], and a dibenzyl sulfoxide solution supported on silica as a stationary phase [185].…”