DETERMINATION OF 4-NONYLPHENOL IN EFFLUENT AND SLUDGE FROM SEWAGE TREATMENT PLANTS

摘要

Quantitative and efficient methods for the determination of 4-nonylphenol (4-NP) in sewage treatment plant (STP) effluent and sludge samples were developed. For effluent, the 4-NP was converted, in situ, into its acetyl derivative with acetic anhydride in the presence of a base. In the case of sewage sludge, 4-NP was subjected to supercritical carbon dioxide extraction and on-line acetylation during the extraction stage. After a silica gel column cleanup, sample extract was analyzed by capillary column gas chromatography/mass spectrometry in the selected ion monitoring mode. Recoveries of 4-NP in spiked samples (1 and 10 mu g/L for effluent and 5 and 50 mu g/g for sludge) were 93% or above with relative standard deviations better than 5%. Detection limits for 4-NP were 0.1 mu g/L for effluent and 0.1 mu g/g for sludge. These methods were applied to the determination of 4-NP in samples collected from Toronto and vicinity STPs. Concentrations of 4-NP from <1 to 30 mu g/L in the effluent and >100 mu g/g in sludge were found.