Electrochemical studies of ionic liquid

This study evaluates the effectiveness of 1-Ethyl-3-methylimidazolium methanesulfonate ([EMIM]MSO3) and 1-Butyl-3-methylimidazolium bromide ([BMIM]Br) as additives in the zinc electrowinning process from a synthetic acidic sulfate electrolyte containing Mn2+ ions. The aim was to compare these ionic liquid additives with traditional gelatin and a previously studied additive ([BMIM]Cl) to understand their impact on current efficiency and cell voltage reduction. The methodology employed galvanostatic measurements to assess cathodic and anodic potentials, focusing on the current efficiency of zinc deposition under controlled conditions. Surface morphology and crystallographic orientations were investigated using scanning electron microscopy (SEM) and X-ray diffraction (XRD). While adjusting additive concentrations, significant reductions in cell voltage were observed, particularly with [EMIM]MSO3 and [BMIM]Br; the latter achieved a notable reduction in Sb5+ ions and resulted in a decreased power consumption of approximately 165 kWh ton−1. Potentiometric polarization and voltammetric studies indicated that both additives exhibit similar polarization behaviors on aluminum electrodes. Overall, these findings suggest that ionic liquids can enhance the efficiency of the zinc electrowinning process.