A composite material, cow dung-doped sludge biochar (Zn@SBC-CD), was synthesized by one-step pyrolysis using ZnCl as an activating agent and applied to a catalytic ozonation process (COP) for methylene blue (MB) removal. SEM, XRD, FTIR, XPS and BET analyses were performed to characterize the biochar (BC) catalysts. Zn@SBC-CD had high graphitization degree, abundant active sites and uniform distribution of Zn on its surface. Complete removal of MB was achieved within 10 min, with a removal rate much higher than that of ozone alone (32.4%), implying the excellent ozone activation performance of Zn@SBC-CD. The influence of experimental parameters on MB removal efficiency was examined. Under the optimum conditions in terms of ozone dose 0.04 mg/mL, catalyst dose 400 mg/L and pH 6.0, COD was completely removed after 20 min. Electron paramagnetic resonance (EPR) analysis revealed radical and non-radical pathways were involved in MB degradation. The Zn@SBC-CD/O system generated superoxide anion radicals (O), which were the main active species for MB removal, through adsorption, transformation, and transfer, Furthermore, Zn@SBC-CD exhibited good reusability and stability in cycling experiments. This study provides a novel approach for the utilization of cow dung and sludge in synthesis of functional biocatalysts and application in organic wastewater treatment.

中文翻译：

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新型牛粪掺杂污泥生物炭作为有效的臭氧催化剂：石墨结构和缺陷之间的协同作用诱导自由基途径

以ZnCl为活化剂，通过一步热解合成了一种复合材料——牛粪掺杂污泥生物炭（Zn@SBC-CD），并将其应用于催化臭氧化工艺（COP）去除亚甲基蓝（MB）。通过 SEM、XRD、FTIR、XPS 和 BET 分析来表征生物炭 (BC) 催化剂。 Zn@SBC-CD石墨化程度高，活性位点丰富，表面Zn分布均匀。 10 min内即可实现MB的完全去除，去除率远高于单独臭氧的去除率（32.4%），表明Zn@SBC-CD具有优异的臭氧活化性能。检查了实验参数对MB去除效率的影响。在臭氧投加量0.04 mg/mL、催化剂投加量400 mg/L、pH 6.0的最佳条件下，20 min后COD完全去除。电子顺磁共振 (EPR) 分析显示自由基和非自由基途径参与 MB 降解。 Zn@SBC-CD/O体系通过吸附、转化和转移产生超氧阴离子自由基（O），这是去除MB的主要活性物种，此外，Zn@SBC-CD在循环实验中表现出良好的可重用性和稳定性。该研究为利用牛粪和污泥合成功能性生物催化剂及其在有机废水处理中的应用提供了新途径。