NaY zeolite-polyethersulfone-modified membranes for the removal of cesium-137 from liquid radioactive waste

Isotope cesium-137 (137Cs) is a major fission product that results from nuclear processes. This radioactive material constitutes a hazardous source of contamination to the environment even at low concentrations. Removal of this harmful radioactive isotope is deemed as an intricate challenge to resolve. The present study aims to synthesize a novel NaYzeolite modified Polyethersulfone (PES) membranes for 137Cs removal from real nuclear liquid waste. The zeolite has been synthesized through hydrothermal method on seedless static aging. Various zeolite contents were then impregnated within the PES membrane matrix to modify the membrane characteristics and ion-exchange properties. Besides, the proposed interaction mechanism of the modified NaYzeolite and PES has been illustrated for the first time in this study. The characteristics of the NaY zeolite, neat PES, and modified membranes were characterized comprehensively via X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), and contact angle (CA) techniques. Results disclosed that optimum removal rate (90.2%) was obtained by the membrane prepared using 0.15% NaY while the decontamination factor (DF) was 10.2 at pH 7.5. Therefore, a legend agent copper ferrocyanides (CuFC) has been added to the feed solution aiming to promote the removal efficiency of 137Cs and enhance the decontamination factor. As a result, about 99.2% Cesium retention and 121.2 decontamination factor were achieved.(c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study successfully developed a modified PES membrane for the removal of cesium-137 from nuclear liquid waste. By adjusting the zeolite content and adding copper ferrocyanides, the removal efficiency and decontamination factor were significantly improved.