Separation of Am, Cm and Lanthanides by Solvent Extraction with Hydrophilic and Lipophilic Organic Ligands

Abstract

The mutual separation of Am, Cm and lanthanides (Ln) by the hydrophilic and lipophilic ligands present in both aqueous and organic phases was studied. The hydrophilic ligands used here are DTPA (diethylene-triamine-N,N,N’,N’’,N’’-pentaacetic acid), malonamide, amic acid, TEDGA (N,N,N’,N’-tetraethyl-diglycolamide) and DOODA(C2) (N,N,N’,N’-tetraethyl-3, 6-dioxaoctanediamide) and four types of extractants, TODGA (N,N,N’,N’-tetraoctyl-diglycolamide), TDdDGA (N,N,N’,N’-tetradodecyl-diglycolamide), DOODA(C8) (N,N,N’,N’-tetraoctyl-3, 6-dioxaoctanediamide) and DOODA(C12) (N,N,N’,N’-tetradodecyl-3, 6-dioxaoctanediamide). DOODA(C8, 12) can extract light lanthanides with high D values into the organic phase. On the other hand (TO, TDd)DGA shows the opposite trend for Ln extraction. The high separation factor, over 1000, between D for La and that for Gd can be seen in the extraction using the extractant, TDdDGA, and DOODA(C2) as the masking agent in the aqueous phase. The separation factors for Am/Cm by DOODA(C8, C12) and (TO, TDd)DGA are 1.51-1.94, while values over 3 can be obtained by the conditions introduced in this work.