Dong Zheng-Yu, Lin Yi-Li, Zhang Tian-Yang, Hu Chen-Yan, Pan Yang, Pan Renjie, Tang Yu-Lin, Xu Bin, Gao Nai-Yun
State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 824, Taiwan, ROC.
Water Res. 2022 Nov 1;226:119200. doi: 10.1016/j.watres.2022.119200. Epub 2022 Oct 3.
To improve the performance of the conventional coagulation process, a permanganate (Mn(VII)) pre-oxidation combined with Fe(III)/peroxymonosulfate (PMS) coagulation process (Mn(VII)-Fe(III)/PMS) that can significantly improve the removal of dissolved organic carbon (DOC), turbidity, and micropollutants is proposed in this study. Compared with conventional Fe(III) coagulation, the Mn(VII)-Fe(III)/PMS process can also significantly enhance the removal of iohexol and sulfamethoxazole in raw water. During this process, the primary reduction product, Mn(IV), after Mn(VII) pre-oxidation was adsorbed on the floc surfaces and involved in the Fe(III)/PMS process. The natural organic matter (NOM) in raw water mediated the redox cycle of iron. The synergistic effect of NOM, Fe, and Mn facilitated the redox cycle of Mn(III)/Mn(IV) and Fe(III)/Fe(II) to promote the activation of PMS. The sulfate radical (SO) played an important role in the degradation of micropollutants. The formation potential of the detected volatile disinfection by-product (DBP) during the subsequent chlorination was reduced by 21.9% after the Mn(VII)-Fe(III)/PMS process. This study demonstrated the promising application of the Mn(VII)-Fe(III)/PMS process for coagulation and micropollutant control and illustrated the reaction mechanism. This study provides guidance for improving conventional drinking water treatment processes.
为提高传统混凝工艺的性能，本研究提出了一种高锰酸盐（Mn(VII)）预氧化与铁（III）/过一硫酸盐（PMS）混凝相结合的工艺（Mn(VII)-Fe(III)/PMS），该工艺能显著提高溶解有机碳（DOC）、浊度和微污染物的去除率。与传统的铁（III）混凝相比，Mn(VII)-Fe(III)/PMS工艺还能显著提高原水中碘海醇和磺胺甲恶唑的去除率。在此过程中，Mn(VII)预氧化后的主要还原产物Mn(IV)吸附在絮体表面，并参与铁（III）/PMS工艺。原水中的天然有机物（NOM）介导了铁的氧化还原循环。NOM、Fe和Mn的协同作用促进了Mn(III)/Mn(IV)和Fe(III)/Fe(II)的氧化还原循环，从而促进了PMS的活化。硫酸根自由基（SO）在微污染物的降解中起重要作用。经过Mn(VII)-Fe(III)/PMS工艺处理后，后续氯化过程中检测到的挥发性消毒副产物（DBP）的生成潜力降低了21.9%。本研究证明了Mn(VII)-Fe(III)/PMS工艺在混凝和微污染物控制方面具有广阔的应用前景，并阐明了反应机理。本研究为改进传统饮用水处理工艺提供了指导。
