Highly Efficient Solvent Extraction of Americium and Europium by Using Hydrogen Dicarbollylcobaltate and N,N′-Diethyl-N,N′-bis(4-ethylphenyl)-1,10-phenanthroline-2,9-dicarboxamide

Solvent extraction of microamounts of Eu3+ and Am3+ from water into nitrobenzene by means of a mixture of hydrogen dicarbollylcobaltate (H+B-) and N,N'-diethyl-N,N'-bis(4-ethylphenyl)-1,10-phenanthroline-2,9-dicarboxamide (L) was studied. The equilibrium data were explained assuming that the species HL+, , , and (M3+ = Eu3+, Am3+; L = N,N'-diethyl-N,N'-bis(4-ethylphenyl)-1,10-phenanthroline-2,9-dicarboxamide) are extracted into the organic phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and are discussed. The reached separation factors SFAm/Eu in this two-phase system are in the range of 19-99. From the experimental results it is apparent that this very effective N,N'-diethyl-N,N'-bis(4-ethylphenyl)-1,10-phenanthroline-2,9-dicarboxamide receptor for the Eu3+ and Am3+ cations could be considered as a potential extraction agent for nuclear waste treatment.