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

A rapid and novel technique was developed to separate long-lived fission products Eu-152 (T-1/2 = 13.33 years) and Cs-137 (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 (similar to 87%) from the mixture of Eu-152 and Cs-137 without any contamination of Cs-137. Simple back extraction using 1 M aqueous HCl from Eu-152-adsorped-ChG leads to pure Eu-152 (similar to 72%). The adsorption behavior of Eu-152 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.