Removal of cobalt from ammonium chloride solutions using a batch cell through an electrogenerative process

• Electrogenerative process as a more environmental friendly metal recovery process.
• Addition of ammonium ions to improve cobalt deposition conditions on reticulated vitreous carbon (RVC).
• Co-deposition of different ions simultaneously.
• Effect of pH on cobalt deposition.

Studies of the removal of cobalt were carried out in a batch cell via an electrogenerative system. Use of electrogenerative systems had successfully demonstrated the feasibility of recovery of co-ions simultaneously. Studies of removal of cobalt from chloride solutions were accomplished using ammonium chloride as a supporting electrolyte. The influence of catholyte and supporting electrolyte concentrations on cobalt recovery were studied by varying the initial cobalt concentrations and ammonium chloride concentration respectively. The results showed that 0.50 M of ammonium chloride was the optimum concentration with <95% of cobalt being removed from an initial Co(II) concentration of 200 mg L−1 in 4 h of operation. A high free energy of −403.89 kJ mole−1 was generated in the electrogenerative process. Cell performance of 85.6% with 100% cobalt recovery was obtained from 200 mg L−1 of Co2+ in 0.5 M NH4Cl. The influence of pH adjustment was examined at pH 7. The morphology of cobalt deposited was also observed by scanning electron microscopy.