An efficient and high-capacity porous functionalized-membranes for uranium recovery from wastewater

Abstract

In order to satisfy the increasing needs for sustainable development of the nuclear energy industry, it is critical to vigorously develop efficient materials for uranium separation and recovery from wastewater. In this work, novel amidoxime-functionalized membranes (PAO membranes) were successfully synthesized via a facile one-step non-solvent induce phase separation rather than as-reported synthesized approaches that needed complicated additives or harsh reaction conditions. The pore channels provided large specific surface areas and massive binding sites, and the bulk-shape membrane was convenient for collection. Removal of uranium as a function of initial pH, reaction time, initial concentrations of U(VI), and temperature was studied. The maximum adsorption capacity of the PAO membranes toward U(VI) calculated from the Langmuir model was up to 641.72 mg·g−1 at pH 5 and 298 K. Thermodynamic studies indicated that the enrichment of U(VI) was a spontaneous and endothermic process. The removal percentage of uranium reached 86.50% in simulated wastewater in the case of multiple coexisting metal ions. In addition, the scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) results confirmed that the abundant adsorption sites of the PAO membranes were responsible for the efficient immobilization of uranium by forming chelating species, especially amidoxime groups and carboxyl groups. This work presents a novel strategy for mass production of a new generation of high-efficiency adsorbents for uranium-containing wastewater treatment in the future.