Chemical separation of actinides from high level radioactive liquid waste using diglycolamide (DGA) compounds

Sasaki, Yuji  ; Kitatsuji, Yoshihiro  ; Sugo, Yumi; Asakura, Toshihide; Kimura, Takaumi 

An innovative chemical separation process for the treatment of high level radioactive liquid waste (HLW) has been developed in our laboratory. There are two main stages in this process. The diglycolamide (DGA) compounds employed for TRU recovery have several advantages, (1) carbon, hydrogen, oxygen and nitrogen atoms in their structures and gasification by combustion, (2) easy synthesis, (3) neutral and tridentate ligands, and (4) strong extraction ability with An from HNO). DGA compounds with the different structures can be obtained by attachment of the different alkyl groups to amidic N atoms, i.e., tetraoctyl-diglycolamide (TODGA), tetradodecyl-diglycolamide (TDdDGA), tetrametyl-diglycolamide (TMDGA) and tetraetyl-diglycolamide (TEDGA). The utility of DGA compounds, which shows the different characters, is revealed and the flow-sheet based on the salt-free concept is exhibited in this paper.