Abstract
In this study, diethylenetriamineperrtaacetic acid (DTPA)-modified magnetic graphene oxide (MGO) was synthesized for removal of Cu(II), Pb(II), arid Cd(II) inns from acidic aqueous solutions. The prepared DTPA/MGO composites were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared and X-ray photoelectron spectroscopies, and zeta potential. The results showed that DTPA successfully functionalized MGO. Adsorption experiments indicated that DTPA/MGO composites exhibited excellent adsorption property in acidic aqueous solutions. The adsorption processed were applicable for the Langmuir adsorption isotherm and the pseudo-second-order model. The maximum adsorption capacities at pH 3.0 for Cu(II)) Pb(II), and CO) ions were 131.4,1387.6, and 286.5 mg/g, respectively. The thermodynamic studies demonstrated that adsorption prOesses were endothermic and spontaneous. Moreover, the DTPA/MGO composites could selectively adsorb Pb(II) from multimetal mixed systems: Adsorption-desorption results showed :that the DTPA/MGO composites exhibited excellent reusability. These results suggested that DTPA/MGO composites have great potential in removing heavy metals from acidic wastewater, especially, for Pb(II).