Comparative study on extraction of copper(II) cations from highly saline media using 2-((phenylimino)methyl)phenol chelating mono-Schiff base /kerosene as novel extractant system

Abstract

The present investigation reports a fundamental extraction- recovery studies of high amount of copper(II) cations from different concentrated saline aqueous solutions including sulphate, chloride, and mixed chloride/ sulphate media with 2-((phenylimino)methyl)phenol extractant (HPIMP) in kerosene at 25 °C. The acid-dissociation constant (Ka) and distribution constant (Kd) between kerosene and various saline aqueous solutions of (HPIMP) were determined. The influence of different parameters namely contact time, organic to aqueous phase (O/A) ratio, pH-value, extractant concentration, and temperature, as well as the effect of anions on the extraction recovery process has been studied. The experimental results revealed that the extraction ability of the (HPIMP) towards Cu(II) ions depends on the nature of inorganic salt. A maximum extraction efficiency of 99.76% was obtained from a 1 M chloride medium, which is significantly higher than those obtained from the sulphate medium (E(%) = 79.13%) or the mixed chloride/sulphate medium (E(%) = 81.75%). The trends in the values of extraction constants were explained in terms of acidity and distribution constants of (HPIMP). From the thermodynamic analysis it is inferred that the extraction process is endothermic and favorable at high temperatures, leading to stable, extractable Cu-HPIMP complexes.