DETERMINATION OF PHENOLIC-COMPOUNDS IN NATURAL-WATERS BY LIQUID-CHROMATOGRAPHY WITH ULTRAVIOLET AND ELECTROCHEMICAL DETECTION AFTER ONLINE TRACE ENRICHMENT

The eleven phenolic EPA priority pollutants were determined by liquid chromatography followed by UV and electrochemical detection. Modified on-line trace enrichment was used to detect lower concentrations of ph enolic compounds, which enables stronger sorbents to be used without b roadening the peaks. PLRP-S and a highly cross-linked styrene-divinylb enzene copolymer were compared for the on-line trace enrichment. Highe r breakthrough volumes were obtained with the latter sorbent but the s electivity was lower. The performance of the methods developed was che cked with tap and river water and the methods studied enabled phenolic compounds at levels of 0.1 mu g l(-1) to be determined in real sample s. The repeatability and reproducibility between days (n = 5) for real samples spiked at 1 mu g l(-1) were lower than 10%.