Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China.
Nanjing Institute of Environmental Science, Ministry of Ecology and Environment of the People's Republic of China, Nanjing, 210042, PR China.
Chemosphere. 2023 Jul;328:138507. doi: 10.1016/j.chemosphere.2023.138507. Epub 2023 Mar 24.
Sulfamethoxazole (SMX) is an extensively applied antibiotic frequently detected in municipal wastewater, which cannot be efficiently removed by conventional biological wastewater processes. In this work, an intimately coupled photocatalysis and biodegradation (ICPB) system consisting of Fe-doped graphitic carbon nitride photocatalyst and biofilm carriers was fabricated to remove SMX. The results of wastewater treatment experiments showed that 81.2 ± 2.1% of SMX was removed in the ICPB system during the 12 h, while only 23.7 ± 4.0% was removed in the biofilm system within the same time. In the ICPB system, photocatalysis played a key role in removing SMX by producing hydroxyl radicals and superoxide radicals. Besides, the synergism between photocatalysis and biodegradation enhanced the mineralization of SMX. To understand the degradation process of SMX, nine degradation products and possible degradation pathways of SMX were analyzed. The results of high throughput sequencing showed that the diversity, abundance, and structure of the biofilm microbial community remained stable in the ICPB system at the end of the experiments, which suggested that microorganisms had accommodated to the environment of the ICPB system. This study could provide insights into the application of the ICPB system in treating antibiotic-contaminated wastewater.
磺胺甲恶唑（SMX）是一种广泛应用的抗生素，经常在城市废水中被检测到，而传统的生物废水处理过程并不能有效地去除它。在这项工作中，我们制备了一种由掺铁石墨相氮化碳光催化剂和生物膜载体组成的紧密耦合光催化和生物降解（ICPB）系统，以去除 SMX。废水处理实验结果表明，在 12 小时内，ICPB 系统中 SMX 的去除率为 81.2±2.1%，而在相同时间内生物膜系统中 SMX 的去除率仅为 23.7±4.0%。在 ICPB 系统中，光催化通过产生羟基自由基和超氧自由基在去除 SMX 方面发挥了关键作用。此外，光催化和生物降解之间的协同作用增强了 SMX 的矿化。为了了解 SMX 的降解过程，分析了 9 种降解产物和 SMX 的可能降解途径。高通量测序的结果表明，在实验结束时，ICPB 系统中的生物膜微生物群落的多样性、丰度和结构保持稳定，这表明微生物已经适应了 ICPB 系统的环境。这项研究可为 ICPB 系统在处理抗生素污染废水中的应用提供思路。
