Homogeneous catalytic activation of peroxymonosulfate and heterogeneous reductive regeneration of Co2+ by MoS2: The pivotal role of pH
Homogeneous catalytic activation of peroxymonosulfate and heterogeneous reductive regeneration of Co2+ by MoS2: The pivotal role of pH
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过一硫酸盐的均相催化活化和 MoS2 对 Co2 的非均相还原再生：pH 的关键作用
DOI：
10.1016/j.scitotenv.2019.136447
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发表时间：
2020
影响因子：
9.8
通讯作者：
Mao Qihang
中科院分区：
文献类型：
--
作者：
Pan Cong;Fu Libin;Ding Yaobin;Peng Xueqin;Mao Qihang
研究了MoS 2在Co（II）/过一硫酸盐（PMS）体系中的应用，并系统地探讨了MoS 2协同催化Co（II）/PMS体系降解有机污染物的催化活性随pH变化的机理.结果表明，MoS_2对Co（II）/PMS体系在pH4.0 ~ 7.0范围内均表现出明显的增敏作用，尤其是在pH5.5和6.0时。在pH为5.5和6.0时，MoS 2-Co2+/PMS体系中罗丹明B（RhB）的准一级反应速率分别是Co2+/PMS体系（Co2+2 μmol L−1，PMS 0.2 mmol L − 1，MoS20.5 g L−1）的3.2和1.8倍. Mo（IV）和S（-II）在MoS 2表面促进了Co 3 +/Co2+的氧化还原循环，再生的Co2+诱导PMS均匀活化，产生了以羟基自由基为主的自由基.在MoS 2-Co（II）/PMS体系中，随着MoS 2投加量、Co2+浓度和PMS浓度的增加，RhB的降解率呈线性增加。此外，MoS_2在MoS_2-Co（II）/PMS体系中具有良好的催化稳定性和化学稳定性。本研究对MoS 2在金属离子/PMS体系中的强化作用有了新的认识，并提供了一种低浓度Co2+时高性能的Co（II）/PMS废水处理工艺。
The application of MoS2to enhance Co(II)/peroxymonosulfate (Co(II)/PMS) system for organic pollutants degradation was developed, and the mechanism for pH dependent catalytic activity in the MoS2co-catalyzed Co(II)/PMS processes was systematically investigated. It was found that MoS2presented enhancement effect for Co(II)/PMS system in the tested pH range from 4.0 to 7.0, especially at pH 5.5 and 6.0. The pseudo first order reaction rates for Rhodamine B (RhB) degradation in MoS2-Co2+/PMS system at pH 5.5 and 6.0 were 3.2 and 1.8 times that in Co2+/PMS system (Co2+2 μmol L−1, PMS 0.2 mmol L−1, MoS20.5 g L−1). The redox recycle of Co3+/Co2+was promoted by Mo(IV) and S(-II) on MoS2surface and regenerated Co2+induced homogeneous activation of PMS for the robust production of free radical with the major of hydroxyl radicals. Increasing MoS2dosage, Co2+and PMS concentration can linearly raise RhB degradation rate in MoS2-Co(II)/PMS system. Moreover, MoS2exhibited excellent catalytic and chemical stability in recyclability and reuse for catalytic decontamination in MoS2-Co(II)/PMS system. This work gains new insight into the enhancement effect of MoS2in the meal ions/PMS system, and provides a high performance wastewater treatment process of Co(II)/PMS at low concentrated Co2+.