Formation of Acidic Trace Organic By-Products from the Chlorination of Humic Acids

摘要

A method for concentrating and analyzing acidic trace organics produced by the chlorination of humic acids at concentrations approximating common drinking water levels is described. Data are compared from several humic acid sources. Specific compound analyses of the extracts were conducted by fused silica capillary column gas chromatography/mass spectrometry. Mass spectral and chromatographic retention data were used to characterize the compounds. Few differences were found in the types of compounds formed from the chlorination of humic acids from the different sources. A notable difference from other published work was the tentative identification of ring-chlorinated methoxy or phenolic aromatic acids. A granular activated carbon concentration column gave better recoveries of a wide range of compounds than an XAD-8 resin column, but some higher molecular weight compounds, particularly aromatics, were recovered more efficiently from the XAD-8 column.