Collect. Czech. Chem. Commun. 1993, 58, 1324-1336

The Extraction of Strontium and Barium with a Solution of Bis-1,2-Dicarbollylcobaltate in Nitrobenzene in the Presence of 18-Crown-6

Petr Vaňuraa and Emanuel Makrlíkb

a Department of Analytical Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6, Czech Republic
b Motorlet, 158 01 Prague 5-Jinonice, Czech Republic


A study has been made of the extraction of Sr and Ba in an aqueous solution of perchloric acid-18-crown-6-bis-1,2-dicarbollylcobaltate-nitrobenzene. It was found that the organic phase contains complexes of the ML2+org type ( M = Sr2+, Ba2+) that are converted to ML22+org when the concentration of crown (cL) is greater than the concentration of bis-1,2-dicarbollylcobaltate (cB). The values of the corresponding extraction constants, individual extraction constants and stability constants of the extracted species in the organic phase were determined. The system can be utilized for separation applications at concentrations here cL < cB.