Beijing Key Laboratory of Bio-inspired Energy Materials and Devices, School of Space & Environment, Beihang University, Shahe Campus, Beijing, 102206, China.
Beijing Drainage Group Co. Ltd (BDG), Beijing, 100044, China.
Chemosphere. 2021 Jun;272:129453. doi: 10.1016/j.chemosphere.2020.129453. Epub 2021 Jan 4.
Triclosan (TCS) is an emerging contaminant that threatens the environment and human health. This study was conducted to investigate TCS abatement by a novel electro-oxidation (EO) process, which used a Ti-based nickel and antimony doped tin oxide (NATO/Ti) anode and a carbon nanotubes (CNTs) doped carbon/PTFE (CNTs-C/PTFE) gas diffusion electrode (GDE) for oxygen reduction reaction (ORR). A comparative study was also performed for TCS degradation by using a traditional EO with a nickel foam cathode, termed as HER-EO. The optimal initial TCS concentration, current density and solution pH for TCS degradation during the ORR-EO and HER-EO were investigated. Results showed that ORR-EO removed more than 98% of TCS in 10-60 min under the concentration of 5-50 mg/L. The TCS degradation followed pseudo-first-order kinetics and its main intermediates were observed during the ORR-EO and HER-EO using liquid chromatography combined mass (LC-MS). The results of FED analysis and toxicity prediction by ECOSAR software showed that less intermediates accumulated during the ORR-EO and the residues were less harmful. The ORR-EO degradation mechanism for TCS was attacking on the ether bond and the benzene ring by OH. This novel ORR-EO process exhibits a great merit in the field of emerging contaminants abatement.
三氯生（TCS）是一种新兴的污染物，对环境和人类健康构成威胁。本研究旨在探讨一种新型电氧化（EO）工艺对 TCS 的去除效果，该工艺采用钛基掺镍和锑锡氧化物（NATO/Ti）阳极和掺碳纳米管的碳/聚四氟乙烯（CNTs-C/PTFE）气体扩散电极（GDE）用于氧还原反应（ORR）。同时，还使用传统的带有镍泡沫阴极的 EO 进行了 TCS 降解的对比研究，称为 HER-EO。研究了 ORR-EO 和 HER-EO 中 TCS 降解的最佳初始 TCS 浓度、电流密度和溶液 pH 值。结果表明，在 5-50mg/L 的浓度下，ORR-EO 在 10-60min 内可去除超过 98%的 TCS。TCS 降解遵循准一级动力学，在 ORR-EO 和 HER-EO 中使用液相色谱-质谱联用（LC-MS）观察到主要的中间产物。FED 分析和 ECOSAR 软件毒性预测的结果表明，在 ORR-EO 过程中中间产物的积累较少，残留产物的危害性较小。ORR-EO 降解 TCS 的机制是通过 OH 攻击醚键和苯环。这种新型的 ORR-EO 工艺在新兴污染物去除领域具有很大的优势。
