Effective capture of aqueous uranium using a novel magnetic goethite: Properties and mechanism

Abstract

A large amount of uranium-containing wastewater is produced by the nuclear industry, which causes harm to human health and the environment. Goethite (α-FeOOH) is highly insoluble in water and has a net positive surface charge, making it an effective sorbent for metal–anion complexes in aqueous solutions. In this study, goethite (α-FeOOH) and Fe2+-modified magnetic goethite (M-α-FeOOH) were prepared using an easy one-pot chemical precipitation method and used to remove uranium from solution. The adsorbents were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), BET surface area analysis, fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM). When Fe2+ partially substitutes for Fe3+, the material is magnetic, has a larger specific surface area and can be rapidly separated in a magnetic field. The uranium adsorption performance of M-α-FeOOH was substantially better than that of α-FeOOH, and its maximum adsorption capacity increased by 46.09%. The data fitted well with the quasi-second order kinetic model and the Langmuir isothermal adsorption model. According to the results of this study, the increase in the uranium removal performance of M-α-FeOOH was attributed to its higher specific surface area, better dispersion, and larger quantity of activated adsorption sites. These results, along with its low-cost, environmentally friendly, and facile synthesis, reveal M-α-FeOOH is a promising material for uranium capture.