Solvent extraction studies of nickel(II) by capric acid from sodium sulfate solution

AbstractThe extraction of nickel(II) from sulfate medium of the ionic strength of 0.33 M by capric acid dissolved in chloroform has been carried out at 25 °C. The stoichiometry of the organometallic complexes extracted was given by using the slope analysis method. Nickel(II) complexes exist as mononuclear species NiL2.2HL and as dinuclear species (NiL2.2HL)2 in low and high capric acid concentrations, respectively. Extraction constants for each species were determined. UV–visible and FT-IR spectroscopy have also been performed for the study of the ligand and their complexes. Electronic spectra of nickel(II) caprate species suggest the octahedral geometry. The present results have been compared with the previous results for the extraction of cobalt(II) and copper(II) and found that the extraction order for capric acid for the three metals is as follows: Cu > Ni > Co.