Removal of heavy metal ions from industrial wastewater using magnetic nanoparticles

In this work, maghemite (gamma-Fe2O3) and magnetite (Fe3O4) nanoparticles were synthesized using coprecipitation method, and characterization was done using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infra-red spectroscopy (FTIR). The size of these particles was found to be in the range from 20 to 100 nm, and these particles were used as nanoadsorbents for the removal of heavy metal ions like chromium and copper from the artificial wastewater. Adsorption depends on the optimum conditions of parameters such as pH (2.5 and 6.5), contact time (60 and 80 minutes), and dosages at room temperature for chromium and copper that were observed with a removal efficiency of 92 %. These particles showed remarkable efficiency in removal of metals. Further, these particles were regenerated for reuse, and desorption was done using HCl and NaOH effluent for copper and chromium metals, respectively. The removals of pollutant enhanced with magnetic nanoparticles are evident with the obtained results. The separation factor (r) lies between 0 and 1, indicating favoring Langmuir isotherm for both chromium and copper ions.