Determination of cobalt in natural water samples after separation and preconcentration by dispersive liquid-liquid microextraction based on the solidification of floating organic drop

Jamali, Mohammad Reza; Rahimpour, Salah; Rahnama, Reyhaneh

doi:10.22075/chem.2017.605

Determination of cobalt in natural water samples after separation and preconcentration by dispersive liquid-liquid microextraction based on the solidification of floating organic drop

Authors

Mohammad Reza Jamali

Salah Rahimpour

Reyhaneh Rahnama

10.22075/chem.2017.605

Abstract

Abstract
A simple, rapid and environmentally friendly method has been developed for the determination of cobalt ions in water samples by dispersive liquidâliquid microextraction based on the solidification of floating organic droplet (DLLME-SFO) coupled with flame atomic absorption spectrometry (FAAS). In this method, cobalt was complexed with 2-nitroso-1-naphthol and extracted into a small volume of 1-dodecanol, which is of low density, low toxicity and proper melting point near room temperature. Several variables that affect the extraction efficiencies, including pH, concentration of chelating agent, type and volume of the extraction solvent and dispersive solvent, extraction time and salt addition, were investigated and optimized. Under the optimized conditions, the limit of detection was 1.6 Âµg Lâ1 with a preconcentration factor of 25 for 25 mL of sample. The proposed method has been successfully applied for the determination of cobalt in real water samples.

Keywords

Dispersive liquid–liquid microextraction

Solidification of floating organic droplet

preconcentration

Cobalt

water samples