ENVR 262 |
| During the chlorination process, natural organic matter (NOM) reacts with chlorine and forms trihalomethanes (THMs). NOM was isolated via resin adsorption into six fractions: hydrophilic base (HPIB), hydrophilic acid (HPIA), hydrophilic neutral (HPIN), hydrophobic base (HPOB), hydrophobic acid (HPOA) and hydrophobic neutral (HPON). The original samples and their six fractions were incubated by chlorine for 7 days and tested for THMs' formation potential (THMFP). Changes to UV absorbance before and after incubation was observed and correlated to THMFP. THMFP results showed that HPOA and HPIN were the most reactive fractions. The HPOA fraction was composed of a highly aromatic structure, which was highly sensitive to its UV absorbance. An obvious reduction of UV absorbance of HPOA after incubation was observed due to the addition of halogen atoms at the conjugate bonds in the aromatic rings. In contrast, HPIN fractions did not have high UV absorbance, but also formed high THMFP. The observations suggested that THMs are not only formed from high UV absorbing organics. |
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Advances in Drinking Water Disinfection and Disinfection Byproduct Management
6:00 PM-8:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster
Division of Environmental Chemistry |