Nanocomposite 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 nanocomposites
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 x1, x2, x3 and x4 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 L1).The optimum
condition was achieved at secondary concentration of 120.18 mg L1 at pH = 3, the initial concentration of
280 mg L1,time of 105 min at 20 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 DGo, DSo and DHo showed that the adsorption
reaction of Pb(II) onto GO/Fe3O4/LA/EDTA was spontaneous and endothermic in nature.
