Chlorella biochar modified with boron and copper (B/Cu-BC) was created and used to break down the antibiotic metronidazole (MNZ) through peroxymonosulfate (PMS) activation. The physicochemical properties of B/Cu-BC were analyzed using SEM, BET, FTIR, XRD and XPS. The results showed that the modified Chlorella biochar, which included several oxygen-containing functional groups, exhibited a rise of 7.1 times in specific surface area and a rise of 8 times in pore volume compared to the unmodified variant. Under the optimal conditions, the B/Cu-BC+PMS system removed 86.6 % of MNZ in 90 min. The reaction mechanism of the system was confirmed by Quenching and electron paramagnetic resonance (EPR) experiments. The B/Cu-BC+PMS system was accompanied by SO4•-, •OH, •O2- and 1O2, in which •O2-was the main reactive oxygen species (ROS). The intermediates in the degradation process of MNZ were investigated using HPLC-MS, and two potential degradation pathways of MNZ were suggested. Finally, the toxicology of the intermediates from the MNZ degradation process was analyzed by toxicity estimation software tool. The bioconcentration coefficients and mutagenicity coefficients showed a significant decrease, indicating that the system could efficiently degrade the antibiotic MNZ in an environmentally friendly manner.

中文翻译：

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使用硼/铜掺杂生物炭活化的甲硝唑降解机制


用硼和铜 （B/Cu-BC） 改性的小球藻生物炭被创造出来，用于通过过氧一硫酸盐 （PMS） 活化分解抗生素甲硝唑 （MNZ）。采用 SEM、BET、FTIR、XRD 和 XPS 分析 B/Cu-BC 的理化性质。结果表明，与未改性变体相比，包含几个含氧官能团的改性小球藻生物炭的比表面积增加了 7.1 倍，孔体积增加了 8 倍。在最佳条件下，B/Cu-BC+PMS 系统在 90 分钟内去除了 86.6 % 的 MNZ。通过淬灭和电子顺磁共振 （EPR） 实验证实了系统的反应机理。B/Cu-BC+PMS 体系伴有 SO4•-、•OH、•O2- 和 1O2，其中•O2-是主要的活性氧 （ROS）。采用 HPLC-MS 研究了 MNZ 降解过程中的中间体，并提出了 MNZ 的两种潜在降解途径。最后，通过毒性估计软件工具分析 MNZ 降解过程中中间体的毒理学。生物富集系数和致突变系数显著降低，表明该系统能够以环保的方式高效降解抗生素 MNZ。