The Modelling Investigation of Wiikit Ore as Radioactive Waste Matrices by Studying Behavior of its U and Th Atoms

This research is dedicated to modeling  the wiikit uranium ore for HLW radioactive waste storing. At first, during X-ray Crystallography it was determined that wiikit has metamict structure. Then SEM revealed the U phase and different mineral phases that could be regarded as a reason for being amorphous. EMP was used to determine the chemical composition of the sample showing that wiikit contains 4% of uranium. The radioactive elements U and Th were separated by ion exchange chromatography using Dowex АВ-17-8 anion exchanger. During the next stage, the U and Th sources were prepared by molecular plating. Alpha-spectroscopy of the U and Th sources revealed high deficit in 234U/238U activity ratios, which violates secular equilibrium in the series of 238U decay. Finally, according to the results obtained by the behavior analysis of the U and Th atoms in this wiikit, modeling of the wiikit as 237Np, 239Pu, 241Am, 242Cm, 244Cm radioactive waste matrices and other heavy radioisotopes was performed when neutral oxides such as Al2O3,SiO2, Fe2O3 were added.