Supercritical fluid extraction of coal tar-contaminated soil samples

Soil samples containing coal tar residues from manufactured gas (town gas) plants were extracted by carbon dioxide supercritical fluid extraction (SFE) and Soxhlet extraction techniques. The detection limits and the reproducibility of the SFE method were evaluated, and the comparability of measured concentrations of polycyclic aromatic hydrocarbons (PAH) by the two extraction methods was determined. Laboratory extracts were analyzed by high-resolution gas chromatography to quantify selected PAH