Screening of silver nanoparticles containing carbonized yeast cells for adsorption of few long-lived active radionuclides

摘要

The present study involves the screening of silver nanoparticles containing carbonized yeast cells isolated from coconut cell sap for efficient adsorption of few long lived radionuclides like 137Cs₅₅, 60Co₂₇, 106Ru₄₄, 239Pu₉₄ and 241Am₉₅. Yeast cells containing silver nanoparticles produced through biological reduction were subjected to carbonization (400 °C for 1 h) at atmospheric conditions and their properties were analyzed using fourier transform infra-red spectroscopy, X-ray diffraction, scanning electron microscope attached with energy dispersive spectroscopy and transmission electron microscope. The average size of the silver nanoparticles present on the surface of the carbonized silver containing yeast cells (CSY) was 19 ± 9 nm. The carbonized control yeast cells without silver exposure (CCY) did not contain any particles on its surface. The efficiency of CSY and CCY towards the radionuclide adsorption was studied in batch mode at fixed contact time, concentration, and at its native pH. CSY was efficient in removal of 239Pu₉₄ (76.75%) and 106Ru₄₄ (54.73%) whereas CCY showed efficient removal only for 241Am₉₅ (62.89%). Both the adsorbents did not show any retention with respect to 60Co₂₇ and 137Cs₅₅. Based on the experimental data, decontamination factor and distribution coefficient (K _d) were calculated and, from the values, it was observed that these adsorbents have greater potential to adsorb radionuclides.