Emanuel Makrlík,a,* Petr Vaňurab and Pavel Seluckýc
a Faculty of Applied Sciences, University of West Bohemia, Husova 11, 306 14
Pilsen, Czech Republic.
b Institute of Chemical Technology, Technická 5, 166 28 Prague 6, Czech Republic
c Nuclear Research Institute, 250 68 Řež, Czech Republic
* Corresponding author: E-mail: makrlik@centrum.cz
Abstract
From extraction experiments and γ-activity measurements, the exchange extraction
constants corresponding to the general
equilibrium M2+(aq) + SrL2+(nb)
↔ ML2+(nb) + Sr2+(aq) taking place in the
two-phase water-nitrobenzene system
(M2+ = Ba2+, Pb2+, Cd2+; L = tetraethyl
p-tert-butylcalix[4]arene tetraacetate;
aq = aqueous phase, nb = nitrobenzene
phase) were evaluated. Further, the stability constants of the ML2+ complexes in
water saturated nitrobenzene were calculated;
they were found to increase in the order Ba2+ < Cd2+ < Pb2+.
Keywords: Barium, lead, cadmium, strontium dicarbollylcobaltate, nitrobenzene, calix[4]arene, extraction and stability constants