| Abstract [eng] |
The environment constantly suffers from human anthropogenic activity. Release of radionuclides into the environment harmfully affects humanity and nature. Therefore, their removal from contaminated liquid media is one of the most important purposes of the environmental protection.Recently, various nanosorbents have been widely used for this purpose due to their efficiency, eco-friendly and specific properties. At the same time, analytical methods are being improved and new promising materials for safe waste disposal are being proposed. The storage of radioactive waste for a long-term requires ensuring the minimum environmental impact, predicting and monitoring of the released radionuclides into the environment and their variations. The dissertation describes the results of a study of the removal of radionuclides using the graphene oxide and the nanocomposites based on it (Prussian blue graphene oxide, magnetic graphene oxide, magnetic Prussian blue graphene oxide and chitosan graphene oxide). The dissertation consists of three sections: literature review, materials and methods, results and discussion. The second section describes the methods of synthesis of nanocomposites and the conditions for radionuclide sorption experiments. Synthesized nanosorbents were characterized by FTIR, XRD, SEM, TEM and RAMAN methods. Using the produced nanocomposites, the sorption experiments were conducted with 134Cs (I), 60Co (II), 241Am (III), 239Pu (IV) and 239Pu (V) as well as Cu (II), Co (II), Ni (II) and Pb (II) as stable radionuclide analogues. The batch technique was used to study the dependence of concentration, initial pH and contact time on the sorption efficiency. Results of these studies are discussed in the third section. Also, the mechanisms of Pu isotope sorption on Šaltiškiai clay minerals were investigated and the changes during the association depending on Pu (IV) spreading in the environment were studied. |
