Free chlorine and free bromine ( e.g. , HOCl and HOBr) are employed as disinfectants in a variety of aqueous systems, including drinking water, wastewater, ballast water, recreational waters, and cleaning products. Yet, the most widely used methods for quantifying free halogens, including those employing N , N -diethyl- p -phenylenediamine (DPD), cannot distinguish between HOCl and HOBr. Herein, we report methods for selectively quantifying free halogens in a variety of aqueous systems using 1,3,5-trimethoxybenzene (TMB). At near-neutral pH, TMB reacted on the order of seconds with HOCl, HOBr, and inorganic bromamines to yield halogenated products that were readily quantifiedmore »
Rapid, high-sensitivity analysis of oxyhalides by non-suppressed ion chromatography-electrospray ionization-mass spectrometry: application to ClO 4 − , ClO 3 − , ClO 2 − , and BrO 3 − quantification during sunlight/chlorine advanced oxidation
A rapid and sensitive method is described for measuring perchlorate (ClO 4 − ), chlorate (ClO 3 − ), chlorite (ClO 2 − ), bromate (BrO 3 − ), and iodate (IO 3 − ) ions in natural and treated waters using non-suppressed ion chromatography with electrospray ionization and tandem mass spectrometry (NS-IC-MS/MS). Major benefits of the NS-IC-MS/MS method include a short analysis time (12 minutes), low limits of quantification for BrO 3 − (0.10 μg L −1 ), ClO 4 − (0.06 μg L −1 ), ClO 3 − (0.80 μg L −1 ), and ClO 2 − (0.40 μg L −1 ), and compatibility with conventional LC-MS/MS instrumentation. Chromatographic separations were generally performed under isocratic conditions with a Thermo Scientific Dionex AS16 column, using a mobile phase of 20% 1 M aqueous methylamine and 80% acetonitrile. The isocratic method can also be optimized for IO 3 − analysis by including a gradient from the isocratic mobile phase to 100% 1 M aqueous methylamine. Four common anions (Cl − , Br − , SO 4 2− , and HCO 3 − /CO 3 2− ), a natural organic matter isolate (Suwannee River NOM), and several real water samples were more »
- Award ID(s):
- 1236303
- Publication Date:
- NSF-PAR ID:
- 10296258
- Journal Name:
- Environmental Science: Water Research & Technology
- Volume:
- 6
- Issue:
- 9
- Page Range or eLocation-ID:
- 2580 to 2596
- ISSN:
- 2053-1400
- Sponsoring Org:
- National Science Foundation
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