Solvent Extraction and Stripping of Fe and Mn from Aqueous Solution Using Ionic Liquids as Extractants

Abstract

In the hydrometallurgical recovery process of Fe and Mn from ores and scrap, hydrochloric acid was used to leach these metals in the aqueous solution. Following this, solvent extraction techniques were employed to recover these metals from the chloride-rich solution. Recently, ionic liquids (ILs) have been widely employed in solvent extraction because of their unique characteristics. In this study, recoveries of Fe and Mn were carried out by using solvent extraction and stripping with ionic liquids, Aliquat 336 and Cyphos IL 101. In the extraction process, the metals were extracted from aqueous solution to organic solution containing IL by the anion exchange reaction between the anion of ionic liquid and the anionic chlorocomplexes such as FeCl4– and MnCl3–. Sodium thiosulfate was the only one stripping agent, which gave the quantitative recovery of Fe (III) from Aliquat 336 solution. Mn (II) was effectively stripped by water from Aliquat 336 solution. The stripping percentages in metal-Cyphos IL 101 system were lower than those of metal-Aliquat 336 system. Aliquat 336 is found to be better extractant than Cyphos IL 101 because of its high stripping performance.