International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Depleted U₃O₈ was mechanically activated in suspension with tributyl phosphate (TBP), trioctylamine (TOA) and ethylenglycolmonomethylether (EGME) in planetary ball mill with stainless steel vessels and balls. X-ray diffractograms and IR spectra of the activated solid samples were taken. The radioactivities of ²³⁸U and ²³⁴Th in the leaching solutions were determined by α/β liquid scintillation spectrometry. The reduction degree of the oxide, the mean crystallite size of U₃O₈ and U₃O₇ and the leaching of ²³⁸U and ²³⁴Th as a result of the mechanoactivation were determined. Higher degree of ²³⁸U and ²³⁴Th leaching was achieved when mechanoactivation with TBP was performed. No leaching of ²³⁸U daughter product (²³⁴Th) proceeded at mechanoactivation with TOA and EGME. The role of the solvents complexation ability, milling induced increase of crystal defect concentration and UO₂ – ThO₂ solid solution formation is discussed. Further studies have to be made to elucidate the potential of the applied approach as a step in spent nuclear fuel processing.