Facile synthesis of hierarchical Fe4(P2O7)3 for removal of U(VI)

Fe-4(P2O7)(3) was successfully synthesized by using high temperature solid state reaction method and characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FT-IR). The as-synthesized Fe-4(P2O7)(3) was applied as adsorbent to adsorb U(VI) ions from aqueous solutions and the material exhibited high sorption capacity for U(VI). The effect of contact time, pH, ionic strength, solid content and temperature on U(VI) sorption to Fe-4(P2O7)(3) was investigated by using batch technique. The results demonstrated that the sorption of U(VI) was independent of ionic strength, indicating that the sorption was mainly dominated by inner-sphere surface complexation. The thermo-dynamic parameters (Delta G(0), Delta S-0 and Delta H-0) were calculated from the temperature-dependent sorption isotherms, and the results suggested that the sorption of U(VI) was a spontaneous and endothermic process. To get a better understanding of the interaction mechanism between U(VI) and Fe-4(P2O7)(3), the U(VI) adsorbed Fe-4(P2O7)(3) was characterized by SEM, XRD and FT-IR. The results might be important for the application of Fe-4(P2O7)(3) in the field of U(VI) pollution management. (C) 2014 Elsevier B.V. All rights reserved.