Alkyl chain structure-dependent separation of Cr(VI) from acidic solutions containing various metal ions using liquid–liquid solvent extraction by butyl-based imidazolium bromide salts

Abstract

In this study, the comparison of Cr(VI) extraction and separation from acidic solutions by solvent extraction technique in presence of Fe(III), Ni(II), Co(II), and Cu(II) was performed using four different symmetric and asymmetric imidazolium salts (IMs)-substituted butyl and isobutyl alkyl groups. The effective parameters on separation and extraction of Cr(VI) were examined in both organic and aqueous phases to identify optimum conditions. Under optimum conditions, symmetric IMs were elected as the best extractive agents and 99.45% of Cr(VI) was extracted and 99.22% of Cr(VI) was effectively stripped with higher separation factors toward the other metal ions.