▎ 摘　　要

Nahocomposite of magnetite graphene oxide/Lauric acid containing ethylenediaminetetraacetic acid nanoparticles (GO/Fe3O4/LA/EDTA) was synthesized in aqueous media by chemical co-precipitation method. Morphology, particle size, structure and physical properties of GO/Fe3O4/LA/EDTA nano composites were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, Energy dispersive X-ray (EDX) spectroscopy, Thermal gravimetric analysis (TGA), Vibrating sample magnetometer (VSM), Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Transmission electron microscopy (TEM)and Brunauer-Emmett-Teller analysis (BET). The effects of independent variables including pH of solution, concentration of Pb(II) ions, contact time and temperature were coded as x(1), x(2), x(3) and x(4) at five levels (-2, -1, 0,1 and 2), in these calculations Y was considered as the response (the secondary concentration of Pb(II) ions in mg L-1).The optimum condition was achieved at secondary concentration of 120.18 mg L-1 at pH = 3, the initial concentration of 280 mg L-1,time of 105 min at 20 degrees C. In addition, GO/Fe3O4/LA/EDTA nanocomposite can be recovered easily using magnetic separation technology. The experimental equilibrium data was fitted well with the Freundlich model while adsorption kinetics had the highest consistency with the pseudo second-order kinetic model. Thermodynamics parameters including Delta G degrees, Delta S degrees and Delta H degrees showed that the adsorption reaction of Pb(II) onto GO/Fe3O4/LA/EDTA was spontaneous and endothermic in nature. (C) 2016 Published by Elsevier B.V.