Please use this identifier to cite or link to this item:
https://doi.org/10.1016/j.watres.2013.01.047
Title: | Rate laws and kinetic modeling of N-ethyl perfluorooctane sulfonamidoethanol (N-EtFOSE) transformation by hydroxyl radical in aqueous solution | Authors: | Nguyen, T.V. Reinhard, M. Gin, K.Y.H. |
Keywords: | Competitive kinetics Hydroxyl radical Kinetic modeling Perfluorooctane sulfonamides Photochemical degradation |
Issue Date: | 1-May-2013 | Citation: | 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 | URI: | http://scholarbank.nus.edu.sg/handle/10635/91165 | ISSN: | 00431354 | DOI: | 10.1016/j.watres.2013.01.047 |
Appears in Collections: | Staff Publications |
Show full item record
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.