Extraction and voltammetric study of association reaction Cs ++TPB −⇌Cs +TPB − in the nitrobenzene phase of a water-nitrobenzene system

Abstract

The association of the caesium ion, Cs +, with the tetraphenylborate anion, TPB −, in a nitrobenzene medium was studied by two independent methods: the radiometric extraction method and the method of cyclic voltammetry at the interface of two immiscible electrolyte solutions (ITIES). Both methods permit the association constant of the reaction Cs + ( n ) + TPB − ( n ) ⇌ K a Cs + TPB − ( n ) to be determined (the letter n denotes the nitrobenzene phase). From the temperature dependence of the association constant, the values of the thermodynamic magnitudes—the reaction enthalpy and entropy of the association reaction—could also be calculated.