Solvent extraction study of actinide elements by N,N'-dimethyl-N,N'-dihexyl-3-oxapentanediamide and thenoyltrifluoroacetone

We have studied the extraction of Eu(III), Am(III), Th(IV), U(VI) and Np(V) by 4 diamides (DMDHOPDA, N,N'-dimethyl-N,N'-di hexyl-3-oxapentanediamide; DHOPDA, N,N'-dihexyl-3-oxapentanediami de; DMDHTPDA, N,N'-dimethyl-N,N'-di hexyl-3-thiopentanediamide; DHTPDA, N,N'-dihexyl-3-thiopentanediam ide) from perchlorate solutions. Synergistic extraction was observed with these diamides and thenoyltrifluoroacetone (TTA) in which the main extraction species determined are M(TTA)3(DA) (M=Eu, Am), Th(TTA)3(DA)(X), UO2(TTA)2(DA) (DA: diamide, X-: ClO4- or CH2ClCOO-). The species, M(DA)3(X)3, M(DA)3(TTA)(X)2, M(DA)2(TTA)2(X) and M(DA)(TTA)3 are observed in the synergistic extraction of DMDHOPDA+TTA. (orig.)