ABSTRACT
Various procedures have been used to isolate organic compounds from non-saline sediments, preparatory to analysis. The simplest methods is direct solvent extraction. Various solvents have been used – n-hexane extracts hydrocarbons, chlorophenols and chlorinated insecticides from sediments prior to analysis by gas chromatography. Benzene also extracts hydrocarbons from sediments. Methanol and acetone extract chlorophylls from algae prior to spectroscopy, thin-layer chromatography or high performance liquid chromatography – methylene dichloride extracts alkyl phosphates, organophosphorus insecticides and herbicides from sediments, and to separate polyaromatic hydrocarbons from fish prior to gas chromatography. Petroleum ether and hexane-acetone are useful for the extraction of non-volatile chloro compounds, chlorinated insecticides and polychlorinated byphenyls from sediments and crustacea. Acetonitrile or acetonitrile followed by methylene dichloride and petroleum ether are useful solvents for isolating miscellaneous unknown organic compounds from fish and sediments, prior to examination by gas chromatography and mass spectrometry to achieve definitive identification.
