Complete electrolysis using a microflow cell with an oil/water interface.

A novel microflow cell with a nitrobenzene (NB)/water (W) interface was developed. A poly(tetrafluoroethylene) membrane filter was employed to prepare the NB/W interface which was formed over a thin channel (0.1 mm thick, 48 cm long) on a silver plate. The silver plate was electrolyzed in advance and served as an Ag/AgCl electrode for controlling the Galvani potential difference across the NB/W interface as well as detecting the current flowing through the interface. Using the microflow cell, complete electrolysis was accomplished for the interfacial transfer of a representative ion (i.e., tetramethylammonium ion). Thus, the present microflow cell was shown to be promising for coulometric (i.e., absolute quantitative) analysis of ions. Also, the microflow cell was shown to be useful for determination of the number of electrons for complicated charge-transfer processes at the oil/water interface.