Extraction of trivalent europium and americium by the synergistic mixture of bis-1,2-dicarbollylcobaltate and N,N,N′,N′-tetraoctyl diglycolamide in highly polar 3-nitro-α,α,α-trifluorotoluene solvent

The extraction of trivalent europium and americium in the system water—HNO3—3-nitro-α,α,α-trifluorotoluene (F-3)—bis-1,2-dicarbollylcobaltate—N,N,N′,N′-tetraoctyl diglycolamide (L) has been investigated. The experimental data were treated by curve-fitting method using the LETAGROP program. It has been found that the complexes $${\text{HL}}_{{}}^{ + }$$ , $${\text{HL}}_{2}^{ + }$$ , $${\text{ML}}_{ 2}^{3 + }$$ , $${\text{ML}}_{ 3}^{3 + }$$ and $${\text{ML}}_{ 4}^{3 + }$$ (M3+ = Eu3+, Am3+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in F-3 saturated with water have been determined. Extraction in this system can be used for separation of lanthanides and minor actinides from PUREX process raffinate.