High-efficient scavenging of U(VI) by magnetic Fe3O4@gelatin composite

In the present study, the surfaces of Fe3O4 nanoparticles were modified by gelatin coating to prepare a magnetic Fe3O4@gelatin composite. The FTIR and zeta potential analysis provided evidence for the successful grafting of gelatin molecules on Fe3O4 surfaces. The Fe3O4@gelatin samples were stable in solution and could be easily separated from the aqueous solution by exposing to an external magnetic field. Batch technique was adopted to evaluate the efficiency of Fe3O4@gelatin composite for scavenging U(VI) under a series of environmental conditions. The sorption reached equilibrium within 5 h and the kinetic data were well simulated by the pseudo-second order model, indicating that the decontamination of U(VI) by Fe3O4@gelatin was a chemisorption process. The ionic strength-independent sorption behaviors suggested that inner-sphere complexation was the dominant uptake mechanism of U(VI). The maximum sorption amount of U(VI) on Fe3O4@gelatin composite at 293 K (herein, 2.74 x 10(-4) mol/g) is considerably higher than a series of reported adsorbents. In addition, the Fe3O4@gelatin sample exhibited good recycling performance for U(VI) removal. The experimental findings herein put forward the feasibility of using Fe3O4@gelatin composite for the treatment of U(VI)-bearing wastewater. (C) 2016 Elsevier B.V. All rights reserved.