Department of Industrial Chemical & Environmental Engineering, Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid, Madrid, Spain.
Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal.
Sci Total Environ. 2021 May 20;770:145299. doi: 10.1016/j.scitotenv.2021.145299. Epub 2021 Jan 21.
The occurrence of micropollutants (MPs) in the aquatic environment poses a threat to the environment and to the human health. The application of sulfate radical-based advanced oxidation processes (SR-AOPs) to eliminate these contaminants has attracted attention in recent years. In this work, the simultaneous degradation of 20 multi-class MPs (classified into 5 main categories, namely antibiotics, beta-blockers, other pharmaceuticals, pesticides, and herbicides) was evaluated for the first time in secondary treated wastewater, by activating peroxymonosulfate (PMS) with UV-A radiation, without any pH adjustment or iron addition. The optimal PMS concentration to remove the spiked target MPs (100 μg L) from wastewater was 0.1 mM, leading to an average degradation of 80% after 60 min, with most of the elimination occurring during the first 5 min. Synergies between radiation and the oxidant were demonstrated and quantified, with an average extent of synergy of 69.1%. The optimized treatment was then tested using non-spiked wastewater, in which 12 out of the 20 target contaminants were detected. Among these, 7 were degraded at some extent, varying from 10.7% (acetamiprid) to 94.4% (ofloxacin), the lower removals being attributed to the quite inferior ratio of MPs to natural organic matter. Phytotoxicity tests carried out with the wastewater before and after photo-activated PMS oxidation revealed a decrease in the toxicity and that the plants were able to grow in the presence of the treated water. Therefore, despite the low degradation rates obtained for some MPs, the treatment effectively reduces the toxicity of the matrix, making the water safer for reuse.
水中微污染物（MPs）的出现对环境和人类健康构成了威胁。近年来，应用基于硫酸根自由基的高级氧化工艺（SR-AOPs）来消除这些污染物引起了人们的关注。在这项工作中，首次在二级处理废水中评估了紫外-A 辐射激活过一硫酸盐（PMS）同时降解 20 种多类 MPs（分为 5 大类，即抗生素、β受体阻滞剂、其他药物、农药和除草剂），无需任何 pH 调整或铁添加。从废水中去除加标目标 MPs（100μg/L）的最佳 PMS 浓度为 0.1mM，60min 后平均降解 80%，大部分去除发生在最初的 5min 内。证明并量化了辐射与氧化剂之间的协同作用，平均协同度为 69.1%。然后使用未加标废水对优化后的处理进行了测试，在废水中检测到了 20 个目标污染物中的 12 个。在这些污染物中，有 7 种被不同程度地降解，从 10.7%（乙酰胺吡咯烷）到 94.4%（氧氟沙星）不等，较低的去除率归因于 MPs 与天然有机物的比例相当低。用废水进行的光激活 PMS 氧化前后的植物毒性试验表明，毒性降低，并且植物能够在处理水存在的情况下生长。因此，尽管一些 MPs 的降解率较低，但该处理有效地降低了基质的毒性，使水更安全地再利用。
