Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Sci Total Environ. 2021 Jun 1;771:145385. doi: 10.1016/j.scitotenv.2021.145385. Epub 2021 Jan 26.
Advanced oxidation processes (AOPs) have been intensely studied for the removal of refractory pollutants because of the strong oxidizing capacity of hydroxyl radical. One of the emerging AOP methods gaining increased attention is bio-electro-Fenton (BEF) which can generate hydroxyl radical in-situ in the cathode chamber using the energy harvested by exoelectrogenic bacteria in the anode. In this study, the feasibility of BEF technology for the removal of metoprolol, a typical micropollutant widely found in the water environment, was for the first time investigated. It was found that applied voltage and working pH had a significant effect on removal efficiency while Fe dosage as catalyst showed a little effect. Besides removal by hydroxyl radical, metoprolol might be adsorbed on the surface of the reactor, electrode, and precipitated with iron sludge, especially at neutral pH. In a batch experiment with a supplied voltage of 0.2 V, pH 3, and a Fe dose of 0.2 mM, the removal rate of metoprolol in the BEF for the synthetic wastewater and the real effluent from the secondary sediment tank was 66% and 55% within 12 h, respectively. A possible degradation pathway was proposed. Then the removal of metoprolol in a continuous flow BEF system was further studied at different hydraulic retention times (HRTs) of 2, 4, and 6 h, about 77%, 92%, and 95% removal was observed. A toxicity test (less than 20% inhibition on bioluminescence) during treatment and energy cost analysis (5.269 × 10 kWh/order/m) in treating 10 μg/L of metoprolol containing wastewater effluent at continuous flow mode implied that the proposed BEF has a potential for wastewater treatment.
高级氧化工艺（AOPs）由于羟基自由基的强氧化能力而被深入研究，用于去除难降解污染物。一种新兴的 AOP 方法——生物电化学-Fenton（BEF）引起了越来越多的关注，它可以在阴极室内利用阳极中产生的外源性细菌产生的能量原位生成羟基自由基。本研究首次考察了 BEF 技术去除典型的水环境中广泛存在的微量污染物美托洛尔的可行性。结果表明，施加电压和工作 pH 值对去除效率有显著影响，而催化剂 Fe 用量影响较小。除了被羟基自由基去除外，美托洛尔可能会被吸附在反应器、电极表面上，并且与铁污泥一起沉淀，尤其是在中性 pH 值下。在施加 0.2 V 电压、pH 值 3 和 0.2 mM Fe 剂量的批处理实验中，BEF 对合成废水和二次沉淀池出水的美托洛尔去除率分别在 12 h 内达到 66%和 55%。提出了一种可能的降解途径。然后，在不同水力停留时间（HRT）为 2、4 和 6 h 的连续流 BEF 系统中进一步研究了美托洛尔的去除情况，观察到约 77%、92%和 95%的去除率。在处理过程中进行了毒性测试（生物发光抑制率小于 20%）和能量成本分析（连续流模式下处理 10μg/L 美托洛尔废水时为 5.269×10 kWh/order/m），表明所提出的 BEF 具有废水处理的潜力。
