Comparison among different extraction methods (PFE, SFE, sonication, Soxhlet) for the isolation of organic compounds from coal

This work presents the results of a study involving modern methodologies, s uch as the ultrasonic extraction, pressurized fluid extraction (PFE) also t ermed accelerated solvent extraction (ASE), and the extraction with supercr itical fluids (SFE) for the isolation of organic compounds from a complex e nvironmental matrix coal. The validation of the results obtained through th ese techniques was carried out by means of comparison with the results obta ined by classical standard extraction method based on Soxhlet. The obtained results demonstrated that SFE present superior performance in the extracti on of organic compounds from coal samples than all other investigated techn iques (PFE or ASE, Ultrasonic, and Soxhlet). On the other hand, SFE present s the worst selectivity for the extraction of some selected classes such as aromatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs). ( C) 2000 John Wiley & Sons, Inc.