Synthesis of Magnetic Graphene Oxide/Chitosan Nanocomposite and Application on Removal of UO²⁺₂ from Aqueous Solution

Magnetic graphene oxide /chitosan (MCGO) nanocomposite was prepared by ultrasonic method using graphene oxide and chitosan as raw materials and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxy succinimide (NHS) as activators, and the adsorption performance of UO²⁺₂ on MCGO was investigated. The results of SEM, FT-IR and XRD show that MCGO is successfully achieved, and the size of Fe₃O₄ is nanoscale. It is found that the MCGO has equilibrium adsorption capacity of 266.67 mg/g at pH=5.5, initial UO²⁺ ₂ concentration of 160 mg/L, adsorption time of 1.5 h and adsorption temperature of 288 K. The experimental equilibrium data were fitted with thermodynamics and kinetics models. The results show that MCGO conforms to Langmuir isotherm model and pseudo-second order kinetic model as well as the adsorption of endothermic spontaneous process. The first re-utilization rate of MCGO is up to 98.47%, and reaches 74.43% after repeatedly adsorbing and desorbing for 6 cycles, which shows that MCGO has a good reusability.