Enhanced extraction of polychlorinated organic compounds from soil samplesby fluidized-bed extraction (FBE)

The extraction and determination of polychlorinated organic compounds, like hexachlorobenzene, pentachlorobenzene, octachlorostyrene and polychlorinat ed biphenyls in soils and solid wastes continues to be a subject for study. In this work Soxhlet extraction and a new extraction technique, fluidized- bed extraction, have been compared. The extraction of polychlorinated organ ic compounds by this technique has been optimized using experiemental desig n procedures. The variation of the number of extraction cycles, composition of extraction solvent (mixtures of n-hexane-acetone) and the holding time after reaching the hearing temperature were considering as experimental var iables to generate a surface response design. Gas chromatography with mass spectrometric detection was used to determine levels of the analytes in the extracts. Extraction and analysis of a certified reference material (BCR C RM 392) showed the applicability of the method.