Removal of Arsenic and Copper from Water Solution Using Magnetic Iron/Bentonite Nanoparticles (Fe3O4/Bentonite)

Heavy metal pollution is one problem in the water purification industry, which causes extreme risk aversion. The purpose of this study was to investigate the removal of arsenic (As) and copper (Cu) from water by nanoparticles of magnetic iron bentonite (Fe3O4/bentonite). Fe3O4/bentonite nanoparticles were prepared by chemical co-precipitation method. The synthesized samples were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction patterns (XRD) techniques. The results of the XRD and FTIR confirmed the successful synthesis of the Fe3O4/bentonite nanoparticles. The results of the SEM showed that the Fe3O4/bentonite nanoparticles had symmetrical, bullet-shaped particles with uniform size. Then, by performing modular experiments, the effect of time, temperature and pH parameters was investigated on the pollutants adsorption rate in an aqueous solution. The results showed that the adsorption capacity for ions increased by increasing the contact time, temperature and adsorbent dosage of the solution The results indicated that the optimum condition was achieved at temperature of 75 degrees C, reaction time of 120 min, the adsorbent dosage of 5 g/l and pH of 6 and 4 for Cu and As, respectively. Langmuir and Freundlich isotherms were employed to modeling of the experimental results. The best results in the modeling prosess for the experiment results were obtained based on the Freundlich isotherm. The kinetic data were also analyzed through pseudo-first-order and pseudo-second-order models. The pseudo-first-order kinetic model well depicted the kinetics of heavy metals ions adsorption on adsorbent.