Fe/Cu Composite Electrode Prepared by Electrodeposition and Its Excellent Behavior in Nitrate Electrochemical Removal

The Fe/Cu electrode, prepared via a cathodic electro-deposition method, was applied as cathode material for electrochemical denitrification and achieved an enhanced NO3−-N removal efficiency. The Fe/Cu electrode was characterized by SEM and EDS. The results showed that nano-Fe particles were evenly distributed on the surface of Cu foam. Compared with Cu foam (24.3%) and Fe (76.0%), the Fe/Cu electrode reached a much higher nitrate removal efficiency (98.6%) within 90 min. Influencing factors of electrolysis such as initial NO3−-N concentration, current density, pH and temperature were further studied, showing that high current density and temperature were conductive to NO3−-N removal. What's more, effect of Cl− on decreasing NH4+-N generation and promoting TN removal was investigated thoroughly. Result presented that addition of 1.0 g L−1 Cl− greatly decreased NH4+-N generation, leading to a 98.2% TN removal efficiency after 3 h treatment. Based on the analysis experimental results, a possible pathway of nitrate electro-reduction was proposed. Additionally, the Fe/Cu composite electrode maintained excellent efficiency and qualified iron leaching, demonstrating its potential application in the treatment of nitrate contaminated water.