Preparation and Study of the Adsorption Performances of (Mg,Ca,Ba)Fe2O4 Magnetic Porous Materials for Removal of Cd(II) Heavy Metal Ion from Water Environment

Abstract A modified polyacrylamide gel route with urea used as fuel was used to synthesize the MFe 2 O 4 (M = Mg, Ca, Ba) iron oxides with high adsorption capacity for removal of Cd(II) from water treatment. The phase structure, functional group, porous structure and adsorption performance of MFe 2 O 4 (M = Mg, Ca, Ba) iron oxides were characterized by X-ray-diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), N 2 adsorption–desorption isotherm and 721 spectrophotometer. The result indicates that the phase forming temperature of MFe 2 O 4 , the content of carbonate ion in MFe 2 O 4 increases with the increasing of the radius of M-site metal ion. The E g value, BET surface area and adsorption capacity for removal of Cd(II) from water treatment decreases with the increasing of the radius of M-site metal ion. The experimental isotherm of MFe 2 O 4 (M = Mg, Ca, Ba) iron oxides were described by the Langmuir model. MgFe 2 O 4 iron oxide exhibits a best adsorption performance for removal of Cd(II) from water treatment by the adsorption process, with a maximum adsorption capacity of ca. 221.36 mg/g than that of other iron oxides. The present synthetic route could be possibly extended to synthesize other porous metal oxide materials with special porous structures for various applications.