Synthesis of Magnetic Iron Oxide Fe3O4/α-Fe2O3 for the Adsorptive Removal of Cadmium from Aqueous Solution

Magnetic iron oxide nanoparticles were successfully synthesized by co-precipitation method. The magnetite and mixture of magnetite/ hematite iron oxide were obtained and characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption/desorption isotherms and vibrating sample magnetometer. These nanoparticles exhibited good adsorbents performance for removal cadmium metal ion. The mixture of magnetite/ hematite particles showed small size of particle and removed cadmium ion rapidly. The rates of Cd removal were 90 and 95% with Fe3O4 and Fe3O4/α-Fe2O3 samples respectively and the pseudo first and second kinetic models were applied to describe adsorption. Langmuir and Freundlich models were used for describing adsorption isotherms.