Oxidative removal of antibiotic resistant E. coli by sulfidated zero-valent iron: Homogeneous vs heterogeneous activation.
Oxidative removal of antibiotic resistant E. coli by sulfidated zero-valent iron: Homogeneous vs heterogeneous activation.
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DOI：
10.1016/j.jhazmat.2020.124411
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发表时间：
2020-10
影响因子：
13.6
通讯作者：
Hui Jin;Zhizhi Cang;Weijing Ding;Wentong Wu;Hongkun Ma;Chenxi Wang;Zhongwei Qi;Zifu Li
中科院分区：
文献类型：
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作者：
Hui Jin;Zhizhi Cang;Weijing Ding;Wentong Wu;Hongkun Ma;Chenxi Wang;Zhongwei Qi;Zifu Li
作为水中的新兴污染物，抗生素耐药细菌正在严重威胁公众健康。在本研究中，硫化 ZVI 用于激活过硫酸盐，以去除抗生素耐药性大肠杆菌和抗生素耐药基因。令人印象深刻的是，在硫化 ZVI 激活的过硫酸盐系统 (S/Fe= 0.05) 中，7 log 的抗生素耐药性大肠杆菌在 30 分钟内被灭活。电子顺磁共振和自由基猝灭实验表明，硫化处理没有改变自由基的种类。 SO 4•− 和HO• 是去除抗生素耐药性大肠杆菌和基因的主要活性氧。对过硫酸盐活化机理的研究表明，过硫酸盐分解主要归因于非均相活化。更重要的是，原位表征（ATR-FTIR）表明主要的电荷转移络合物形成在硫化ZVI的表面上，这将主要介导SO 4•−和HO•的生成。最后，对所提出的系统在水和二级废水建模方面进行了评估。结果显示，在 NOM (10 mg/L) 和 HCO 3–(84 mg/L) 存在下，抗生素耐药性大肠杆菌分别仅被灭活 2.86 log 和 0.84 log。此外，硫化ZVI活化过硫酸盐系统在实际废水处理中可能具有pH依赖性。
As an emerging contaminant in water, antibiotic resistant bacteria are threatening the public health gravely. In this study, sulfidated ZVI was used to activate persulfate, for antibiotic resistant E. coli and antibiotic resistant genes removal. Impressively, 7 log of antibiotic resistant E. coli was inactivated within 30 min, in sulfidated ZVI activated persulfate system (S/Fe= 0.05). Electron paramagnetic resonance and free radical quenching experiments suggested that sulfidation treatment did not change the specie of radicals. SO 4•− and HO• were the main reactive oxygen species for the removal of antibiotic resistant E. coli and genes. Investigation on the activation mechanism of persulfate indicated that persulfate decomposition was mainly attributed to heterogeneous activation. More importantly, in-situ characterization (ATR-FTIR) indicated that the main charge transfer complex was formed on the surface of sulfidated ZVI, which would predominantly mediate the generation of SO 4•− and HO•. Finally, the proposed system was evaluated in modeling water and secondary effluent. Results revealed that only 2.86 log and 0.84 log of antibiotic resistant E. coli were inactivated in the presence of NOM (10 mg/L) and HCO 3–(84 mg/L), respectively. Besides, sulfidated ZVI activated persulfate system could be pH-dependent in actual wastewater treatment.