Determination of organic pollutants in reagent water by liquid-solid extraction followed by supercritical fluid elution.

ABSTRACT

A selected group of polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides, and phthalate esters in reagent water containing no particulate matter were separated and identified by liquid-solid extraction and supercritical fluid extraction (SFE). The water sample is first passed through a cartridge or disk containing a solid matrix coated with a chemically bonded C18 organic phase capable of extracting those organic compounds. The cartridge or the disk is then eluted with supercritical carbon dioxide to remove the compounds from the sorbent. Finally, the extract is injected into a capillary column gas chromatographic/quadruple mass spectrometric system. The precisions, percent recoveries of analytes using solvent elution, and percent recoveries using SFE are compared. The total analysis time is greatly reduced by using disk extraction and SFE in place of cartridge extraction and liquid-solvent elution. In addition, the waste solvent generated was minimized by using SFE.