Please use this identifier to cite or link to this item:
|Title:||Rate laws and kinetic modeling of N-ethyl perfluorooctane sulfonamidoethanol (N-EtFOSE) transformation by hydroxyl radical in aqueous solution|
|Authors:||Nguyen, T.V. |
|Source:||Nguyen, T.V., Reinhard, M., Gin, K.Y.H. (2013-05-01). Rate laws and kinetic modeling of N-ethyl perfluorooctane sulfonamidoethanol (N-EtFOSE) transformation by hydroxyl radical in aqueous solution. Water Research 47 (7) : 2241-2250. ScholarBank@NUS Repository. https://doi.org/10.1016/j.watres.2013.01.047|
|Abstract:||The degradation of perfluorochemicals (PFCs) by hydroxyl radical (OH) follows complex pathways resulting in stable products. Kinetic models are needed to predict the product distribution of OH-initiated PFC degradation under environmental and treatment conditions. The bimolecular rate constants were measured in water for the reaction of OH and N-ethyl perfluorooctane sulfonamidoethanol (N-EtFOSE), and intermediates, N-ethyl perfluorooctane sulfonamidoacetate (N-EtFOSAA), N-ethyl perfluorooctane sulfonamide (N-EtFOSA) and perfluorooctane sulfonamidoacetate (FOSAA). Under standard conditions (pH = 6, 25 ± 2 °C, Co PFC = 5-10 μg L-1, Co H2O2 = 10 mM, irradiation intensity = 765 W m-2), the measured constants for N-EtFOSE, N-EtFOSAA, N-EtFOSA and FOSAA were (1.05 ± 0.12) × 109 M-1 s-1, (0.68 ± 0.05) × 109 M-1 s-1, (0.68 ± 0.05) × 109 M-1 s-1 and (0.53 ± 0.05) × 109 M-1 s-1, respectively. Constants in the pH range from 1 to 10 varied within a factor of 2-4 for most compounds. Over a period of 2-days, N-EtFOSE reacted directly (without forming long-lived intermediates) to perfluorooctane sulfonamide (FOSA) (18.8%) and perfluorooctanoic acid (PFOA) (39.1%). N-EtFOSE reacted via oxidation of the ethanolic hydroxyl group to N-EtFOSAA (12.4%) and N-dealkylation to N-EtFOSA (13.3%) and FOSAA (0.2%) and unknown intermediates. In sunlit surface waters, the OH-induced transformation of N-substituted sulfonamide compounds to photostable products occurs on a time scale of days to weeks by model prediction. © 2013 Elsevier Ltd.|
|Source Title:||Water Research|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Feb 21, 2018
WEB OF SCIENCETM
checked on Jan 16, 2018
checked on Feb 18, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.