Efficient decontamination of organic pollutants under high salinity conditions by a nonradical peroxymonosulfate activation system
Efficient decontamination of organic pollutants under high salinity conditions by a nonradical peroxymonosulfate activation system
复制标题
非自由基过一硫酸盐活化体系在高盐度条件下高效净化有机污染物
DOI：
10.1016/j.watres.2020.116799
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发表时间：
2021-01-13
期刊：
影响因子：
12.8
通讯作者：
Yu, Han-Qing
中科院分区：
文献类型：
--
作者：
Chen, Fei;Liu, Lian-Lian;Yu, Han-Qing
基于过一硫酸盐（PMS）的高级氧化工艺（AOPs）用于废水处理最近引起了广泛关注。然而，通过传统的自由基主导途径降解有机污染物受到自由基与共存无机阴离子之间的副反应的严重限制，特别是在高盐度条件下。在此，合成了一种高效的Fe/O共掺杂的g - C₃N₄纳米片催化剂，其主要通过单线态氧和高价铁 - 氧物种（Fe(V)=O）的双重非自由基途径激活PMS。在模拟的高盐废水（≥200 mM）中，通过投加PMS（1 mM）、催化剂（0.1 g/L），所开发的Fe/O掺杂的g - C₃N₄ + PMS体系对模型污染物双酚A（BPA）实现了快速降解，其反应速率常数比g - C₃N₄ + PMS体系高1204倍。O和Fe共掺杂剂能够重构原始g - C₃N₄的电子结构以产生更多的非自由基活性物种。形成的Fe(V)=O通过促进电子从BPA分子转移到“亚稳态PMS/催化剂复合物”，在BPA降解中起主要作用，这通过电化学测试和密度泛函理论计算得到了验证。·OH + SO₄·⁻物种的辅助瞬态产物也有利于污染物的降解。在较宽的pH范围内具有优异的重复使用性，证实了Fe/O掺杂的g - C₃N₄ + PMS体系的实际应用前景。向富含污染物的体系中连续添加低剂量的PMS被证实有利于PMS的利用。我们的工作揭示了非自由基主导的工艺在含盐水中有机污染物净化方面的潜在应用。（c）2021爱思唯尔有限公司。保留所有权利。
Peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) for wastewater treatment have recently attracted widespread interests. However, the degradation of organic pollutants via traditional radical-dominated pathway is severely limited by the side reactions between radicals and the coexisting inorganic anions, especially under high salinity conditions. Herein, an efficient Fe/O co-doped g-C(3)N(4)nanosheet catalyst was synthesized to dominantly activate PMS through a dual non-radical pathway with the singlet oxygen and high-valent iron-oxo species (Fe(V) = O). The rapid degradation of model pollutant bisphenol A (BPA) was achieved by dosing PMS (1 mM), catalyst (0.1 g/L) in a simulated high salt wastewater (>= 200 mM) of the developed Fe/O-doped g-C3N4 + PMS system with a reaction rate constant of 1204-fold higher than that in g-C3N4 + PMS system. The O and Fe co-dopants could reconfigurate the electronic structure of pristine g-C3N4 to produce more non-radical active species. The formed Fe(V) = O played a main role in the BPA degradation by promoting electron transfer from BPA molecule to the "metastable PMS/catalyst complex", which was verified by electrochemical tests and density functional theory calculations. The auxiliary transient productions of center dot OH + SO4 center dot- species were also favorable for the pollutant degradation. Excellent reusability in a wide pH range confirmed the practical application prospects of the Fe/O-doped g-C3N4 + PMS system. The successive addition of PMS with a low dosage into the system rich in pollutants was confirmed to favor the PMS utilization. Our work unveils the potential applications of a non-radical dominated process for the decontamination of organic pollutants in saline water. (c) 2021 Elsevier Ltd. All rights reserved.