Please use this identifier to cite or link to this item:
|Title:||Kinetic assessment of the potassium ferrate(VI) oxidation of antibacterial drug sulfamethoxazole|
|Citation:||Sharma, V.K., Mishra, S.K., Ray, A.K. (2006-01). Kinetic assessment of the potassium ferrate(VI) oxidation of antibacterial drug sulfamethoxazole. Chemosphere 62 (1) : 128-134. ScholarBank@NUS Repository. https://doi.org/10.1016/j.chemosphere.2005.03.095|
|Abstract:||Sulfamethoxazole (SMX), a worldwide-applied antibacterial drug, was recently found in surface waters and in secondary wastewater effluents, which may result in ecotoxical effects in the environment. Herein, removal of SMX by environmentally-friendly oxidant, potassium ferrate(VI) (K2FeO 4), is sought by studying the kinetics of the reaction between Fe(VI) and SMX as a function of pH (6.93-9.50) and temperature (15-45°C). The rate law for the oxidation of SMX by Fe(VI) is first-order with respect to each reactant. The observed second-order rate constant decreased non-linearly from 1.33 ± 0.08 × 103 M-1 s-1 to 1.33 ± 0.10 × 100 M-1 s-1 with an increase of pH from 7.00 to 9.50. This is related to protonation of Fe(VI) (HFeO4-⇔H++FeO42-; pKa,HFeO4 = 7.23) and sulfamethoxazole (SH ⇔ H+ + S-; pKa,SH = 5.7). The estimated rate constants were k11 (HFeO4-+SH)=3.0×104 M-1 s-1, k12 (HFeO4-+S-)=1.7×102 M-1 s -1, and k13 (FeO42-+SH)=1.2×100 M-1 s-1. The energy of activation at pH 7.0 was found to be 1.86 ± 0.04 kJ mol-1. If excess potassium ferrate(VI) concentration (10 μM) is used than the SMX in water, the half-life of the reaction using a rate constant obtained in our study would be approximately 2 min at pH 7. The reaction rates are pH dependent; thus, so are the half-lives of the reactions. The results suggest that K2FeO4 has the potential to serve as an oxidative treatment chemical for removing SMX in water.|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Jul 22, 2018
WEB OF SCIENCETM
checked on Jun 20, 2018
checked on Jun 1, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.