TY - JOUR
T1 - Kinetics and mechanism of thiamethoxam abatement by ozonation and ozone-based advanced oxidation processes
AU - Wang, Huijiao
AU - Zhan, Juhong
AU - Gao, Lingwei
AU - Yu, Gang
AU - Komarneni, Sridhar
AU - Wang, Yujue
N1 - Funding Information:
This study is funded by the NSFC project ( 51878370 ), the National Special Program of Water Pollution Control and Management ( 2017ZX07202 ), the special fund of State Key Joint Laboratory of Environment Simulation and Pollution Control ( 18L01ESPC ), and the National Postdoctoral Program for Innovative Talents ( BX20180161 ).
Funding Information:
This study is funded by the NSFC project (51878370), the National Special Program of Water Pollution Control and Management (2017ZX07202), the special fund of State Key Joint Laboratory of Environment Simulation and Pollution Control (18L01ESPC), and the National Postdoctoral Program for Innovative Talents (BX20180161).
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/5/15
Y1 - 2020/5/15
N2 - In this study, the abatement of neonicotinoid insecticide, thiamethoxam, by single ozonation, ozone/ultraviolet (O3/UV) and electro-peroxone (EP) process was evaluated. The second-order rate constants for the reaction of thiamethoxam with O3 and hydroxyl radical ([rad]OH) at pH 7 were determined to be 15.4 M–1 s–1 and 3.9 × 109 M–1 s–1, respectively. The degradation pathways of thiamethoxam were proposed based on quantum chemical calculations and transformation products were identified using chromatographic and mass-spectrometric techniques. The acute and chronic toxicity of thiamethoxam and its major TPs to various aquatic organisms were assessed. With typical ozone doses applied in water treatment (≤5 mg/L), thiamethoxam was abated by only ∼16–32 % in two real water matrices (groundwater and surface water) during single ozonation, but by ∼100 % and >70 % during the O3/UV and EP treatment, respectively. The energy demand to abate 90 % thiamethoxam in the two water matrices was generally comparable for single ozonation and the EP process (∼0.14 ± 0.03 kW h/m3), but higher for the O3/UV process (0.21–0.22 kW h/m3). These results suggest that single ozonation is unable to sufficiently abate thiamethoxam under typical conditions of water treatment. Therefore, ozone-based advanced oxidation processes are needed to enhance thiamethoxam abatement.
AB - In this study, the abatement of neonicotinoid insecticide, thiamethoxam, by single ozonation, ozone/ultraviolet (O3/UV) and electro-peroxone (EP) process was evaluated. The second-order rate constants for the reaction of thiamethoxam with O3 and hydroxyl radical ([rad]OH) at pH 7 were determined to be 15.4 M–1 s–1 and 3.9 × 109 M–1 s–1, respectively. The degradation pathways of thiamethoxam were proposed based on quantum chemical calculations and transformation products were identified using chromatographic and mass-spectrometric techniques. The acute and chronic toxicity of thiamethoxam and its major TPs to various aquatic organisms were assessed. With typical ozone doses applied in water treatment (≤5 mg/L), thiamethoxam was abated by only ∼16–32 % in two real water matrices (groundwater and surface water) during single ozonation, but by ∼100 % and >70 % during the O3/UV and EP treatment, respectively. The energy demand to abate 90 % thiamethoxam in the two water matrices was generally comparable for single ozonation and the EP process (∼0.14 ± 0.03 kW h/m3), but higher for the O3/UV process (0.21–0.22 kW h/m3). These results suggest that single ozonation is unable to sufficiently abate thiamethoxam under typical conditions of water treatment. Therefore, ozone-based advanced oxidation processes are needed to enhance thiamethoxam abatement.
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U2 - 10.1016/j.jhazmat.2020.122180
DO - 10.1016/j.jhazmat.2020.122180
M3 - Article
C2 - 32006850
AN - SCOPUS:85078475829
SN - 0304-3894
VL - 390
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
M1 - 122180
ER -