Flow-through heterogeneous electro-Fenton system using a bifunctional FeOCl/carbon cloth/activated carbon fiber cathode for efficient degradation of trimethoprim at neutral pH.
Environ Res
; 222: 115303, 2023 04 01.
Article
em En
| MEDLINE
| ID: mdl-36642126
ABSTRACT
The synthesis of multifunctional cathode with high-efficiency and stable catalytic activity for simultaneously producing and activating H2O2 is an effective way for promoting the performance of heterogeneous electro-Fenton process (HEF). In addition, accelerating mass transfer by adopting a flow-through reactor is also great importance because of its better utilization of catalysts and adequate contact of the contaminant with the oxidants generated on the electrode surface. Herein, a novel flow-through HEF (FHEF) system was designed for the degradation of trimethoprim (TMP) using bifunctional cathode with a sandwich structure FeOCl nanosheets loaded onto carbon cloth (CC) and activated carbon fiber (ACF) (FeOCl/CC/ACF). The cathode exhibited excellent performance in activating H2O2 for the in-situ generation of hydroxyl radicals (â¢OH). The electron spin resonance (ESR) measurements and radical quenching tests proved that the high production of â¢OH in the FHEF process was favorable to the high catalytic efficiency. 25 mg L-1 TMP was entirely degraded after 60 min, with the TOC removal of 62.6% (180 min) at pH 6.8, 9.0 mA cm-2, and flux rate 210 mL min-1. Moreover, the degradation rate still could reach 83% (60 min) after 10 cycles without obvious valence and crystal phase changes. Simultaneously, the current utilization rate has also been greatly enhanced, with an average current efficiency of 69.9% and a low energy consumption of 0.28 kWh kg-1. The reasonable degradation pathways for TMP were proposed based on the UPLC-QTOF-MS/MS results. Finally, the results of toxicological simulation showed a declining trend in the toxicity of the samples during TMP degradation. These results claim that the FeOCl/CC/ACF-FHEF system is an efficient and economical technology for the treatment of organic contaminants in effluents.
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Base de dados:
MEDLINE
Assunto principal:
Trimetoprima
/
Poluentes Químicos da Água
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article