▎ 摘　　要

Partially reduced graphene oxide-Fe3O4 composite(PRGO-Fe3O4) was prepared by one step co-precipitation onto graphene oxide(GO) synthesized by modified Hummers method. The as obtained composite was characterized by XRD, FESEM, EDX, HRTEM, SAED, XPS and FTIR. The impact of pH, contact time, dosage, foreign substances, reduction of GO and cycle times on the adsorption performance of the composite towards Mn(II) were investigated and the dsorption isotherm, thermodynamics and kinetics were analyzed. The results indicate that Fe3O4 distribute evenly and uniformly in the as-obtained composite, with a fine particle size of 15-20 nm, resulting in a low remanence and coercivity. The composite shows efficient adsorption property and good recycability towards aqueous Mn(II) owing to the thin GO sheets in its structure caused by the anchoring effect of Fe3O4. Adsorption equilibrium was reached within 3 min with the adsorption percent and capacity of 99-35% and 404-49 mg/g, respectively, under the conditions of pH=7, dosage 500 mg/L, and initial concentration of Mn(II) of 201-32 mg/L, with the subsequent magnetic separation taking only 10 s. After five consecutive cycles, the adsorption capacity of the composite remians 78% that of the first cycle. Analyses on the mechanism and thermodynamics show that the adsorption is an endothermic, spontaneous and monolayer chemical adsorption step.