Abstract: | A chromatographic column was constructed which could be operated with an electrically conductive stationary phase of graphite particles. This column allowed chromatographic experiments at variable electric potentials of the column material. The chromatographic behavior of selected carboxylic acids was significantly influenced at positive column potentials. An equimolar mixture of three different carboxylic acids were separated at a potential of +600 mV (versus. Ag/AgCl). Surprisingly, the stereoisomers maleic and fumaric acid, which are identical in molecular mass and charge, could also be separated. Further improvements to the chromatographic performance were achieved by applying potential drops and linear potential gradients. |