SELECTIVITY OF LIQUID MEMBRANE-ELECTRODE BASED ON MERCURATED POLYSTYRENE AS ION-EXCHANGER TO ANIONIC SURFACTANTS AND SOAPS

An electrode that employs a solution of mercurated polystyrene in 1,1',2,2' tetrachloroethane as the sensor in a liquid-state membrane has been developed. The electrode was tested toward some common anions, anionic surfactants, and soaps. This electrode displays an unusually high level of selectivity for anionic surfactants, in particular to bis(2-ethylhexyl)sodium sulfosuccinate, sodium dodecylbenzenesulfonate, and sodium dodecylsulfate, over many common anions, such as NO3-, ClO4-, F-, Cl-, and Br-. The electrode may find application in the analysis of surfactants, as an indicator electrode in the potentiometric titration and in the physicochemical studies of surfactant solutions.