Overlooked role of CO3·- reactivity with different dissociation forms of organic micropollutants in degradation kinetics modeling: A case study of fluoxetine degradation in a UV/peroxymonosulfate system.
J Hazard Mater
; 478: 135538, 2024 Aug 15.
Article
en En
| MEDLINE
| ID: mdl-39173383
ABSTRACT
Selective oxidizing agent carbonate radical (CO3â¢-) is an important secondary radical in radical-based advanced oxidation technology for wastewater treatment. However, the role of CO3â¢- in removing ionizable organic micropollutants (OMs) under environmentally relevant conditions remains unclear. Herein we investigated CO3â¢- effect on degradation kinetics of fluoxetine in UV/peroxymonosulfate (PMS) system based on a built radical model considering CO3â¢- reactivity differences with its different dissociation forms. Results revealed that the model, which incorporated CO3â¢- selective reactivity (with determined second-order rate constants, ksrc,CO3·-, of 7.33 ×106 and 2.56 ×108 M-1s-1 for cationic and neutral fluoxetine, respectively) provided significantly more accurate predictions of fluoxetine degradation rates (k). A good linear correlation was observed between ksrc,CO3·- from experiments and literatures for 24 ionizable OMs and their molecular orbital energy gaps and oxidation potentials, suggesting the possible electron transfer reaction mechanism. Cl- slightly reduced the degradation rates of fluoxetine owing to rapid transformation of Cl⢠with HCO3- into CO3â¢-, which partially compensated for the quenching effects of Cl- on HO⢠and SO4â¢-. Dissolved organic matter significantly quenched reactive radicals. The constructed kinetic model successfully predicted fluoxetine degradation rates in real waters, with CO3â¢- being the dominant contributor (â¼90 %) to this degradation process.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Hazard Mater
Asunto de la revista:
SAUDE AMBIENTAL
Año:
2024
Tipo del documento:
Article
País de afiliación:
China