Radiation influencing of the extraction properties of the CyMe₄-BTBP and CyMe₄-BTPhen solvents with FS-13

The radiolytic stability of two ligands, CyMe4-BTBP and CyMe4-BTPhen in system with the FS-13 (phenyl trifluoromethyl sulfone) diluent was investigated under irradiation by accelerated electrons to study impact of the degradation products on the separation process efficiency and safety. Irradiation experiments were carried out up to the absorbed dose of 200 kGy. The irradiated samples were analysed by HPLC for the degree of extractant degradation. In addition, the effect of the presence of HNO₃ during the irradiation was studied. Extraction properties of the irradiated solvents were evaluated and compared with the extraction properties of non-irradiated solvents to assess the impact of the degradation products on extractions properties. The results obtained show that the stabilities of these ligands are higher in FS-13 than in the cyclohexanone-type solvents. The extraction properties are significantly influenced by degradation products contained in these systems. Surprisingly, both the distribution ratios for americium and europium, and the Am/Eu separation factor increase with the absorbed dose for the system withCyMe₄-BTPhen in FS-13. Obviously, the degradation products of this ligand are efficient extractants too. In the next phase, an attempt will be done to identify the main degradation products, synthesise them and study their extraction properties. (authors)