Abstract
The extraction of U(VI) and Pu(IV) from aqueous nitrate solutions by N,N'-tetrabutylglutaramide (TBGA) has been investigated. At low acidities, the extraction takes place via the formation of respectively UO2(NO3)2. TBGA and Pu(NO3)4. TBGA which seem to be linked with additionnal molecules of TBGA in the second coordination sphere of the metal. When the saturation of TBGA by UO2 2+solutions is reached, the uranyl complex reorganizes to give a polymer (UO2(NO3)2 TBGA)x. At high acidities, the anionic complexes : [UO2(NO3)3, ] [HTBGA+] and probably [HPu(NO3)6−] [HTBGA+] are observed.