近日，大湾区城市环境安全与绿色发展教育部重点实验室博士高源以第一作者，学术骨干江进教授为通讯作者的题为“Enhanced Peroxymonosulfate Activation via Complexed Mn(II): A Novel Non-Radical Oxidation Mechanism Involving Manganese Intermediates “的学术论文在国际环境领域著名期刊Water Research杂志上发表。

    论文DOI：https://doi.org/10.1016/j.watres.2021.116856

过渡金属催化过硫酸盐是一种常见的高级氧化工艺，对于处理水中有机污染物有较大潜力。近年来研究发现，除硫酸根自由基、羟基自由基外，高活性的变价态金属在过渡金属催化过硫酸盐过程中发挥了重要作用。研究人员在铁离子、铜离子催化过硫酸盐过程中均发现了变价态金属（如Fe(IV)、Cu(III)）的存在。如何区分过渡金属催化过硫酸盐过程中的自由基与非自由基路径成为了近期研究的焦点。不同于铁离子、铜离子等过渡金属对过硫酸盐的高效催化效能，锰离子（Mn(II)）对过硫酸盐的催化效能极低。受络合剂可提高过渡态锰稳定性的启发，本文首次研究了不同金属络合剂对Mn(II)催化过硫酸盐的影响，以期在Mn(II)富集水环境中利用过硫酸盐实现有机物的高效降解，并进一步加深对Mn(II)催化过硫酸盐的化学认知。

英文摘要：

In recent years, the activation of persulfates (peroxydisulfate (PDS) and peroxymonosulfate (PMS)) via transition metal ions for contaminants degradation has received extensive attention in water treatment. There has been growing interest on the mechanism (radical versus non-radical pathway) of activation processes. Interestingly, in contrast to copper, iron or cobalt ions regarded as effective activators for persulfates, manganese ion (Mn(II)) is inefficient for persulfates activation. Inspired by the enhanced stability of manganese species by ligands, this study for the first time systematically investigated the Mn(II)/persulfates with different ligands as a novel oxidation technology. UV-vis spectrometry, chemical probing method and mass spectrometry were used to explore the reactive intermediate (free radical versus high-valent manganese species) therein. It was surprisingly found that the oxidation efficiency of Mn(II)/ligand/persulfates system was highly dependent on the nature of persulfates and ligands. Mn(II) chelated by amino ligands such as ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetate (NTA) could efficiently trigger the oxidation of contaminants (e.g., recalcitrant compounds nitrophenol, benzoic acid and atrazine) by PMS, suggesting a promising Mn(II)/ligand/PMS technology for environmental decontamination especially under manganese-rich conditions. High-valent Mn species (Mn(V)) but not free radicals was demonstrated to be the dominant reactive intermediate, where Mn(III) species played a vital role in Mn(V) generation. The formation of Mn(III) species was found to be affected by the reactivity of persulfates and the type of ligands, thus influencing its further oxidation to Mn(V) species. This study presents a new oxidation process based on the combination of PMS and Mn(II) complex and broadens the knowledge of persulfates activation as well as manganese chemistry for decontamination in water treatment.