Extraction of hexaconazole from weathered soils: A comparison between Soxhlet extraction, microwave-assisted extraction, supercritical fluid extraction and accelerated solvent extraction

Extraction of hexaconazole residues which had been weathered over periods of time varying between 0 and 52 weeks was undertaken from two characterized soils. The various extraction techniques considered were Soxhlet extraction, microwave-assisted extraction, supercritical fluid extraction and accelerated solvent extraction. The results indicated that the physico-chemical properties of the soil are an important factor in the extraction of weathered residues of hexaconazole from soil. Overall the results obtained by accelerated solvent extraction were comparable to those obtained by Soxhlet extraction. Some matrix dependence of supercritical fluid extraction and microwave-assisted extraction was noted for the aged (52 week) sampled sandy loam soil. This effect was not evident for any of the extraction techniques using the sandy clay soil. The best precision was obtained for the automated accelerated solvent extraction system.