Solvent extraction of microamounts of strontium and barium into nitrobenzene using hydrogen dicarbollylcobaltate in the presence of polyethylene glycol PEG 600

Abstract

Extraction of microamounts of strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of polyethylene glycol PEG 600 (L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, H2L2+, ML2+ and MHL3+ (M2+ = Sr2+, Ba2+) 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 water-saturated nitrobenzene the stability constant of the BaL2+ cationic complex species is essentially higher than that of the complex SrL2+.