▎ 摘 要
Novel magnetic graphene oxide-based Cr(III) ion-imprinted materials were prepared through surface ionic imprinting technology. The resulting composites were verified by X-ray diffraction, transmission electron microscopy, atomic force microscopy, Fourier transform infrared spectrometer, Raman spectroscopy, and thermogravimetric analysis techniques. Batch adsorption studies were performed to evaluate adsorption kinetics, isotherms, selectivity, and reusability. The intra-particular diffusion model was best described by adsorption kinetics, whereas adsorption equilibrium data were better described by Langmuir equation. Langmuir dimensionless separation factor calculation results indicated highly favorable adsorption with increased adsorption efficiency at higher Cr(III) ion concentrations. The relative selectivity coefficients of Fe3O4/SiO2-GO-IIP for Cr(III)/Na(I), Cr(III)/Mg(II), and Cr(III)/Ca(II) were 2.68, 2.10, and 2.83 times greater than those of Fe3O4/SiO2-GO-NIP, respectively. In addition, reusability without obvious deterioration in performance was demonstrated by the resulting composites in at least five repeated cycles. The experimental results showed that Fe3O4/SiO2-GO-IIP had high affinity and excellent selectivity for Cr(III) ion, as well as reusability and faster magnetic separation under an external magnetic field.