Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control, Key Laboratory of Petrochemical Pollution Control of Guangdong Higher Education Institutes, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, Guangdong, 525000, China.
Department of Environmental Sciences, College of Earth and Environment Sciences, Lanzhou University, Lanzhou, 730000, China.
Chemosphere. 2023 Mar;318:137970. doi: 10.1016/j.chemosphere.2023.137970. Epub 2023 Jan 25.
In this work, a heterogeneous catalyst of CuO was rationally designed by using Cu-based metal organic frameworks (marked Cu-BDC) as the template, and was used to degrade tetracycline (TC) via activation of peroxymonosulfate (PMS). The optimal CuO-350 showed excellent catalytic efficiency for TC degradation, and the reaction rate constant (0.104 min) was 8 times higher than that (0.013 min) of raw Cu-BDC. The characterization observations confirmed that CuO-350 possessed multiple valence states (CuO and CuO) and oxygen vacancies (O), both of which were favorable for the activation of PMS, resulting in promoting the generation of active species in the CuO-350 + PMS system. Different from the free radical pathway in Cu-BDC + PMS system, a radical-nonradical coupling process was detected in the CuO-350 + PMS system, which was confirmed by quenching experiments and EPR measurements. Moreover, the toxicity prediction showed that the toxicity of degradation intermediates declined compared with TC. This work not only opened up a new strategy for the rational design and preparation of high-efficient catalysts by employing metal organic frameworks precursors, but also offered an insight into the reaction mechanism of PMS activation through a radical-nonradical coupling process catalyzed by CuO-350 derived from Cu-BDC.
在这项工作中，我们通过使用基于铜的金属有机骨架（标记为 Cu-BDC）作为模板，合理设计了一种氧化铜（CuO）的多相催化剂，并通过过一硫酸盐（PMS）的激活来降解四环素（TC）。最佳的 CuO-350 对 TC 降解表现出优异的催化效率，其反应速率常数（0.104 min）是原始 Cu-BDC（0.013 min）的 8 倍。表征观察证实，CuO-350 具有多种价态（CuO 和 CuO）和氧空位（O），这两者都有利于 PMS 的激活，从而促进 CuO-350 + PMS 体系中活性物质的生成。与 Cu-BDC + PMS 体系中的自由基途径不同，在 CuO-350 + PMS 体系中检测到了自由基-非自由基偶联过程，这通过淬灭实验和 EPR 测量得到了证实。此外，毒性预测表明，与 TC 相比，降解中间产物的毒性下降。这项工作不仅为利用金属有机骨架前体制备高效催化剂的合理设计和制备开辟了新的策略，而且通过 CuO-350 介导的自由基-非自由基偶联过程揭示了 PMS 激活的反应机制。
