SUPPORTED LIQUID MEMBRANE WORK-UP IN COMBINATION WITH LIQUID-CHROMATOGRAPHY AND ELECTROCHEMICAL DETECTION FOR THE DETERMINATION OF CHLORINATED PHENOLS IN NATURAL-WATER SAMPLES

A sample preparation method has been developed for the determination o f chlorinated phenols in water. The method is based on a supported liq uid membrane extraction system connected on-line to liquid chromatogra phy with electrochemical detection. The supported liquid membrane tech nique utilizes a porous PTFE membrane. The membrane is impregnated wit h an organic solvent which forms a barrier between two aqueous phases and enables selective extraction. The technique can easily be coupled in a flow system. In this investigation five chlorinated phenols (1-5 chlorine atoms) were extracted from natural water samples. Extraction for 30 minutes resulted in detection limits of approximately 25 ng L(- 1).