Biosynthesis of MgFe2O4 magnetic nanoparticles and its application in photo-degradation of malachite green dye and kinetic study

In this study, we have reported the green synthesis magnesium ferrite using tragacanth gel by the sol-gel method without using any organic chemicals. The sample was characterized by powder X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), vibrating sample magnetometer (VSM) and scanning electron microscopy (SEM). The X-ray powder diffraction (XRD) analysis revealed the formation of cubic phase ferrite MNPs. Magnetic analysis showed that the MgFe2O4 had a superparamagnetic behavior with a saturation magnetization of 14 emu/g at room temperature. The present catalyst displays high photocatalytic activity for the removal of malachite green dye under irradiation with visible light. The effects of MgFe2O4 dosage, initial dye concentration and visible light irradiation on dye degradation were evaluated. The results demonstrated that the catalyst can degrade ca. 98% of the malachite green dye. The catalyst can be easily recovered by a simple magnetic separation and can be recycled six times with no significant loss of photocatalytic activity.