Chen Jia-Qi, Zhou Guan-Nan, Ding Rong-Rong, Li Qi, Zhao Han-Qing, Mu Yang
CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, China.
CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, China; State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution, China University of Geosciences, Wuhan 430078, China.
J Hazard Mater. 2023 Oct 5;459:132229. doi: 10.1016/j.jhazmat.2023.132229. Epub 2023 Aug 5.
In this study, the performance and mechanism of the integrated sulfidated nanosized zero-valent iron and ferrous ions (S-nZVI/Fe) system for oxygen activation to remove emerging contaminants (ECs) were comprehensively explored. The S-nZVI/Fe system exhibited a 2.4-8.2 times of increase in the pseudo-first order kinetic rate constant for the oxidative degradation of various ECs compared to the S-nZVI system under aerobic conditions, whereas negligible removal was observed in both nZVI and nZVI/Fe systems. Moreover, remarkable EC mineralization efficiency and benign detoxification capacity were also demonstrated in the S-nZVI/Fe system. We revealed that dosing Fe promoted the corrosion of S-nZVI by maintaining an acidic solution pH, which was conducive to O activation by dissolved Fe and surface-absorbed Fe(II) to produce •OH. Furthermore, the generation of H* was enhanced for the further reduction of Fe(III) and HO to Fe(II) and •O, resulting in the improvement of consecutive single-electron O activation for •OH production. Additionally, bisphenol A (BPA) degradation by S-nZVI/Fe was positively correlated with the S-nZVI dosage, with an optimum S/Fe molar ratio of 0.15. The Fenton-like degradation process by S-nZVI/Fe was pH-insensitive, indicating its robust performance over a wide pH range. This study provides valuable insights for the practical implementation of nZVI-based technology in achieving high-efficiency removal of ECs from water.
在本研究中，全面探究了硫化纳米零价铁与亚铁离子集成体系（S-nZVI/Fe）对氧的活化作用以去除新兴污染物（ECs）的性能及机制。与有氧条件下的S-nZVI体系相比，S-nZVI/Fe体系对各种ECs氧化降解的准一级动力学速率常数提高了2.4至8.2倍，而在nZVI和nZVI/Fe体系中均观察到可忽略不计的去除效果。此外，S-nZVI/Fe体系还表现出显著的EC矿化效率和良好的解毒能力。我们发现，投加铁通过维持酸性溶液pH促进了S-nZVI的腐蚀，这有利于溶解态铁和表面吸附的Fe(II)活化O以产生•OH。此外，H*的生成增强，可进一步将Fe(III)和HO还原为Fe(II)和•O，从而改善连续单电子O活化以生成•OH。另外，S-nZVI/Fe对双酚A（BPA）的降解与S-nZVI投加量呈正相关，最佳S/Fe摩尔比为0.15。S-nZVI/Fe的类芬顿降解过程对pH不敏感，表明其在较宽pH范围内具有稳健的性能。本研究为基于nZVI的技术在实现从水中高效去除ECs的实际应用中提供了有价值的见解。
