Greener solvents for recovery of cobalt, deep eutectic solvents (DESs) and ionic liquids (ILs), are drawing much attention due to their unique chemical and physical properties.9, 10 Several DESs have been studied to leach cobalt from LiCoO2 and cobalt oxides (Co3O4) in the literature.5 However, recovery of leached Co2+ using the electrodeposition approach in DES has not been given much attention. Electrodeposition has been considered a more sustainable, cost effective and efficient approach to recover leached Co2+ compared to the solvent extraction and chemical precipitation.5
This research work is focused on the electrochemical recovery of cobalt using environmentally friendly ethylene glycol based solvent systems at lower temperature (50 °C). Cyclic voltammetry was used to study the effect of anion and chemical composition of the solvent system on the electrochemical behaviour of cobalt. UV- Vis spectrophotometer was used to identify the coordination geometry of Co2+ in each solvent system. The surface morphologies of the deposited cobalt samples were examined using scanning electron microscopy (SEM). X-ray photo electron microscopy (XPS) and energy dispersive x-ray spectroscopy (EDX) were conducted to analyse the purity of the electrodeposited cobalt samples.
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