Application of gas chromatography-mass spectrometry preceded by solvent extraction to determine volatile fatty acids in wastewater of municipal, animal farm and landfill origin

摘要

This study describes extraction of selected volatile fatty acids (VFAs) (containing from 2 up to 8ncarbon atoms) with methyl-tert-butyl ether (MTBE) from polluted aqueous samples followed bynseparation, identification and quantification by gas chromatography coupled with massnspectrometry (GC-MS). Extraction parameters such as time and number of extractions, volumenratio, effect of acidification and salt addition were optimized with respect to recovery, enrichmentnfactor and repeatability. The VFAs studied were separated using an open tubular capillary columnnStabilwax-DA (crossbond polyethylene glycol treated with nitroterephtalic acid). The limits ofnquantitation (LOQ) of the procedure developed were on the level of 0.1 to 0.5 mg Lu00021. The analysisnof real samples of municipal raw and treated wastewater, animal farms wastewater, and alsonlandfill leachates showed that always dominant was acetic acid. The content of VFAs in animalnfarms wastewater was a few times higher than in municipal wastewater and in municipal solidnwaste landfill leachates. In surface and ground water close to municipal landfill only acetic acidnwas detected at higher concentrations in outflow than inflow water. This indicates that slightnleakage from the landfill must have occurred.