Enhancement of Fe-C micro-electrolysis in water by magnetic field: Mechanism, influential factors and application effectiveness

Abstract

Fe-C micro-electrolysis system has been widely used in filters, or as an advanced treatment process in some water treatment plants to treat various wastewater. In this study, Fe-C micro-electrolysis process was enhanced by an economical and environmentally friendly method, applied magnetic field. Batch kinetic experiments and scanning electron micrographs demonstrated a more effective micro-electrolysis and more severely corroded on the surface of Fe-C after applying a magnetic field at pH 3.0. An applied magnetic field reduced the charge-transfer resistance and increased the current density in micro-electrolysis system and Fe-C became more prone to electrochemical corrosion. Corrosion products were proved to be Fe2+, Fe3O4, and C−O, moreover, the formation of them were also increased in the presence of a magnetic field. Base on that, some influential factors like magnetic field flux intensity, Fe-C particle size, pH, Fe-C dosage and its reusability were investigated in this paper. Since Fe2+ release was accelerated in micro-electrolysis system by an applied magnetic field, combination of various advanced oxidation processes were designed to explore the application effectiveness of the system. The degradation rate of target contaminant was significantly improved in the presence of a magnetic field, suggesting it could be a reliable method for wastewater treatment.