REMOVAL OF YTTRIUM RADIOISOTOPES USING ELECTROSPUN NANOFIBERS AND THEIR UIO-66 COMPOSITES

Abstract

The production of novel materials for effective radionuclide removal from the environment is a necessary strategy before stabilization and disposal. Radionuclides found in nuclear waste, power plants, and industrial and medical wastewater pose a significant environmental risk, especially in the event of a nuclear power plant accident. Yttrium isotopes, commonly associated with nuclear activities and radiopharmaceutical applications, require attention due to their potential mobility in the environment. This study investigates the sorption efficiency of electrospun polymer materials toward ⁹⁰Y³⁺ ions from aqueous solutions. The applied materials include nanofibrous membranes, made of poly(methyl methacrylate) (PMMA), polyamide (PA), and PA-based metal-organic framework (MOF) composites, containing 1% and 10% of UiO-66 MOF. Batch sorption experiments were conducted in synthetic seawater (pH 8.1) and river water (pH 5.7) over intervals from 1 minute to 72 hours. The highest removal efficiency was achieved after 72 hours at pH 5.7 by PMMA (95.9%) and PA (94%), while the results for composites were slightly lower, but comparable (~92%). Microstructural and morphological characterization of the electrospun membrane samples was conducted using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) analysis. The presence of crystalline and amorphous phases was identified in all samples. A defined fibrous structure was confirmed. Changes in the FTIR spectra at 1400-1500 cm^-1 indicated the interactions between ⁹⁰Y³⁺ ions and functional groups within the PA and PMMA membranes. The results suggest that electrospun PMMA and PA-based membranes and composites have significant potential for yttrium radioisotope removal from aquatic bodies.