Use of open tubular trapping columns for on-line extraction-GC of organic compounds from aqueous samples

The applicability of open tubular trapping columns for on-line extraction-GC is evaluated. The extraction step involves sorption of the analytes from water into the stationary phase of an open tubular column, removal of water by purging of the trap with nitrogen and desorption of the analytes with an organic solvent. The effect of swelling the stationary phase with organic solvents on the retention power of the trap (2 m x 0.32 mm Ld.) is studied. When using chloroform as a swelling agent breakthrough volumes higher than 5 rol are obtained for a number of medium polar compounds. For desorption 75 J.Ll of organic solvent are needed. Solvent elimination prior to transfer to the GC column is carried out using a PTV injector and a multidimensional GC system. As an example the extraction of priority pollutants from river water is shown.