Solvent extraction of microamounts of strontium and barium into nitrobenzene by using synergistic mixture of hydrogen dicarbollylcobaltate and dicyclohexano-18-crown-6

摘要

Extraction of microamounts of strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H~+B~-) in the presence of dicyclohexano-18-crown-6 (DCH18C6, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL~+, HL_2~+, ML~(2+) and ML_2}~(2+) (M~(2+) = Sr~(2+), Ba~(2+)) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. It was found that in the mentioned medium the stability constants of the complexes BaL~(2+) and BaL_2}~(2+) where L = DCH18C6, are somewhat higher than those of the species SrL~(2+) and $$ SrL_2~(2+) with the same ligand L.