Selective separation of 152Eu from a mixture of 152Eu and 137Cs using a chitosan based hydrogel

Abstract

A rapid and novel technique was developed to separate long-lived fission products ¹⁵²Eu (T_1/2 = 13.33 years) and ¹³⁷Cs (T_1/2 = 30.17 years) using a solid liquid extraction (SLX) technique with a chitosan biopolymer based hydrogel (ChG). In this technique, ChG selectively adsorped ¹⁵²Eu (∼87%) from the mixture of ¹⁵²Eu and ¹³⁷Cs without any contamination of ¹³⁷Cs. Simple back extraction using 1 M aqueous HCl from ¹⁵²Eu-adsorped-ChG leads to pure ¹⁵²Eu (∼72%). The adsorption behavior of ¹⁵²Eu on ChG depends on pH and radiation dose. The structural, mechanical, thermal and morphological characterization of ChG was confirmed by FT-IR, solid state NMR, rheology measurement, SEM, TG-DTG, DSC and XRD studies. The rheological study shows a higher value of the storage modulus (G′) than the loss modulus (G′′), demonstrating that the rheological behavior in the ChG has a majority of visco elastic solid nature.