VOLTAMMETRIC INTERPRETATION OF ION TRANSFER COUPLED WITH ELECTRON-TRANSFER AT A LIQUID LIQUID INTERFACE

Ion transfer coupled with an electron transfer at an aqueous (W)/nitrobenzene (NB) interface was investigated. The ion transfer reactions studied were those of K+ and Na+ facilitated by valinomycin or dibenzo-18-crown-6 from W to NB and those of such anions as ClO4-, SCN- and I- from W to NB. The electron transfer reaction was Fe(CN)6(3-)/Fe(CN)6(4-) in W and 7,7,8,8-tetracyanoquinodimethane (TCNQ)/TCNQ.- in NB. Referring to the polarograms for the ion and electron transfer recorded at the W/NB interface, the interaction between these processes was elucidated quantitatively. The interaction depends not only on standard transfer energies for both transfers, but also on the ratio of redox agents in W or NB. The separation of ions based on the interaction is also discussed.