Iranian Journal of

Background and Objectives: Increased growing nuclear industry has increased the researchers concerns on uranium presence in the environment and its effects on human health. Uranium is a dangerous radioactive heavy metal with high half-life and chemical toxicity. Therefore, the main objective of this study was to removal uranium (VI) from aqueous solution by uranium benzamide complex using AC_Fe3O4 nanocomposite. Materials and Methods: AC_Fe3O4 nanocomposite was synthesized using co-precipitation method. The experiments were designed as one factor at the time method. The optimum range of pH, contact time, amounts of adsorbent, and concentration of benzamide were determined. Then, kinetic and isotherm of uranium adsorption were studied. In addition, the properties of this adsorbent were characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). Results: The SEM and FTIR analysis confirmed that activated carbon is coated with Fe3O4 nanoparticles and the magnetic property of AC-Fe₂O₃ was approved. According to the results, the optimum conditions were pH =6, contact time =30 min, and 0.06 g of adsorbent dose. The adsorption of uranium on the AC_Fe₃O₄ nanocomposite fitted to Langmuir isotherm and pseudo-second order kinetic model. The removal of U(VI) was increased about 6% with increasing in benzamide concentration to 50 mg/L. The best percentage removal of uranium in aqueous solution was 95%. Conclusion: The removal of U(VI) on AC_Fe₃O₄ nanocomposite with the aid of benzamide is a rapid and highly pH depended process. The maximum sorption capacity (15/87 mg/g) of AC_Fe₃O₄ nanocomposite shows that this method is a suitable method for Uranium removal.