Nitrate Reduction in an Intensified Electrochemical System: Effects of Different Metallic Particles

The performance of nitrate reduction in an electrochemical system intensified by different metallic particles was evaluated in the present study. In the electrochemical process without metallic particles, the nitrate removal efficiency was found to be 65.7%, while higher nitrate conversion yields of 82.9%, 87.5% and 93.2% were obtained in the developed system in the presence of iron, steel and copper particles, respectively. Moreover, the presence of metallic particles in the electrochemical process significantly reduced 39.3-49.5% of the energy consumptions for nitrate reduction. Mechanisms of the acceleration of nitrate reduction by the three metallic particles were different. Iron and steel particles in the middle of the electric field dissolved and served as electron donors for nitrate reduction, while the copper particles worked as activated metallic catalysts. Taking into account of safety and operating cost, iron was the optimal choice among the three metallic particles studied.