Development of dispersive liquid-liquid microextraction based on deep eutectic solvent using as complexing agent and extraction solvent: application for extraction of heavy metals

Abstract

ABSTRACT A green and efficient dispersive liquid-liquid microextraction method based on a new deep eutectic solvent has been developed for the preconcentration and extraction of cobalt and nickel ions. The deep eutectic solvent is formed by mixing choline chloride (hydrogen bond acceptor) and 4-aminophenol (hydrogen bond donor). Then, it is used as a chelating agent as well as extraction solvent. Under the optimum experimental conditions, the linear ranges for Ni(II) and Co(II) were 0.80–50 and 0.50–50 µgL−1, respectively, by flame atomic absorption spectrometry. The obtained detection limits were 0.30 and 0.22 µg L−1 for Ni(II) and Co(II), respectively. Abbreviations ChCl: choline chloride; DES: deep eutectic solvent; DLLME: dispersive liquid-liquid microextraction; EF: enrichment factor; ER: extraction recovery; FAAS: flame atomic absorption spectrometry; LOD: limit of detection; LOQ: limit of quantification.