Radiolytic degradation of hydrophilic PyTri ligands for minor actinide recycling

The 2,6-bis[1H-1,2,3-triazol-4-yl]-pyridine (PyTri) chelating unit has already shown promising properties for application to advanced hydrometallurgical processes aimed at recovering minor actinides from highly active raffinate. Radiolytic stability is an undeniable key requirement for chemicals involved in highly radioactive solutions partitioning, since radiolysis can have a huge impact on system safety and performances. In this work, the radiolytic degradation of two hydrophilic PyTri complexing agents was investigated by different analytical techniques. The radiation damage was delivered by a Co-60 source. The main radiation-induced ligand degradation by-products were hypothesized. Unprecedented PyTri ligands radiolytic stability was proved, further recommending their implementation in future partitioning processes.