Properties of magnetic iron oxides used as materials for wastewater treatment

The paper describes the properties of some nanopowders obtained by coprecipitation and used as adsorbent for wastewater treatment. The Fe₃O₄ and γ-Fe₂O₃ nanopowders were obtained using iron salts and NaOH as precipitation agents. D-sorbitol was used to prevent the agglomeration between the nanoparticles. The particle size and distribution were detected using a transmission electron microscopy (TEM) and a scanning electron microscope (SEM) equipped with dispersive analyze system in X radiation energy (EDS). The structure of the iron oxide nanoparticles was characterized by X-ray powder diffraction. Thus, the nanoparticles were characterized and compare in terms of particle size and chemical composition and used for adsorption studies in order to removal hexavalent chromium from waste waters.