Novel Magnetite-Polymer Nanocomposite for the Removal of Some Radionuclides: Modeling and Performance Evaluation of Fixed-Bed Column Adsorption

Abstract

In this work, a nanocomposite based on magnetite and poly (2-acrylamido-2methyl propane sulfonic acid sodium salt-co-maleic acid-co-styrene) was prepared by gammainduced polymerization at 20 kGy. The average particle size of magnetic nanoparticles was 30 nm, as revealed by transmission electron microscopy, and their saturation magnetization was 79.6 emu g −1 as measured by VSM. FTIR results proved the formation of the magnetite polymer nanocomposite (MPNC), and SEM investigation showed its porous morphology. The nanocomposite was used to remove 137 Cs, (152+154) Eu, and 99 Mo radionuclides from water. The batch adsorption experiment showed that the optimum conditions for adsorption are 60 min of contact time at pH 5. For the three investigated ions, the breakthrough curves produced from the fixed-bed column adsorption experiment show that the exhaustion time (t e ) decreases as the feed flow rate increases and increases as the height of the fixed-bed column increases. The breakthrough curves were modeled using the Thomas and Yoon-Nelson models. The Thomas model provided the greatest fit. The calculated value of Thomas adsorption capacity q Th is close to the experimental value, which could be useful in anticipating scaling-up. The results further demonstrate that the prepared polymer magnetic nanocomposite is extremely selective for (152+154) Eu with a high separation factor.