Sono-assisted degradation of rhodamine B using the Fe modified MgO nanostructures: characterization and catalytic activity.

The present work describes the removal of Rhodamine B (Rh B), a model of organic dye, from aqueous solution by Sono-assisted catalytic process on magnesium oxide- iron (MgO–Fe) nanostructures as catalyst. This material was prepared by high-energy ball milling method and characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM) coupled with EDS analyzer, specific surface analysis determined from by BET analysis and FTIR spectroscopy. The XRD patterns show the formation of the MgFe₂O₄ phase, which presents a face-centred cubic lattice after 1 h of milling. The BET surface area and total pore volume of the spinel were found to be 60 m²/g and 61cm³. The SEM micrographs show that the particles size is between 50 and 100 μm. The best sonocatalytic degradation of Rh B was obtained with MgO–Fe at 12 h of grinding with an almost complete Rh B degradation in 240 min. irradiation time. The results clearly demonstrated the applicability of this MgO–Fe catalyst for the sono-catalytic oxidation of Rh B (10 mg /L). The Rh B mineralization was confirmed by Chemical Oxygen Demand (COD) and High-Performance Liquid Chromatography (HPLC) analysis. [ABSTRACT FROM AUTHOR]