Solvent Extraction of Microamounts of Europium and Americium into Nitrobenzene by Using Hydrogen Dicarbollylcobaltate in the Presence of “classical” CMPO

Emanuel Makrlík^a*, Petr Vaňura^b and Pavel Selucký^c

^a Faculty of Applied Sciences, University of West Bohemia, Husova 11, 306 14 Pilsen, Czech Republic.
^b Institute of Chemical Technology, Prague, Technická 5, 166 28 Prague, Czech Republic
^c Nuclear Research Institute, 250 68 Řež, Czech Republic
* Corresponding author: E-mail:makrlik@centrum.cz

Abstract
Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H⁺B^–) in the presence of octyl-phenyl – N,N – diisobutylcarbamoylmethyl phosphine oxide (“classical” CMPO, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL⁺, HL⁺₂, ML³⁺₂, ML³⁺₃ and ML³⁺₄, (M3+ = Eu³⁺, Am³⁺) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

Keywords: Europium, americium, hydrogen dicarbollylcobaltate, CMPO, extraction and stability constants, water-nitrobenzene system