State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
State Key Laboratory of Urban Water Resources and Environments (SKLURE), School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
Chemosphere. 2022 Sep;302:134868. doi: 10.1016/j.chemosphere.2022.134868. Epub 2022 May 6.
In this study, nitrogen self-doping layered graphitic biochar (Na-BC900) was prepared by catalytic pyrolysis of lotus leaves at 900 C, in the presence of NaCl catalyst, for peroxydisulfate (PDS) activation and sulfamethoxazole (SMX) degradation. NaCl as catalyst played a crucial part in the preparation of Na-BC900 and could be reused. The SMX degradation rate in Na-BC900/PDS system was 12 times higher than that in un-modified biochar (BC900)/PDS system. The excellent performance of Na-BC900 for PDS activation was attributed to its large specific surface areas (SSAs), the enhanced graphitization structure and the high graphitic N content. The quenching and electrochemical experiments, electron paramagnetic resonance (EPR) studies inferred that the radicals included SO, OH, O and the non-radical processes were driven by O and biochar mediated electron migration. Both radical and non-radical mechanisms contributed to the removal of SMX. Additionally, this catalytic pyrolysis strategy was clarified to be scalable, which can be applied to produce multiple biomass-based biochar catalysts for restoration of polluted water bodies.
在这项研究中，氮自掺杂层状石墨生物炭（Na-BC900）是通过在 900°C 下在 NaCl 催化剂存在下催化热解荷叶制备的，用于过二硫酸盐（PDS）活化和磺胺甲恶唑（SMX）降解。NaCl 作为催化剂在 Na-BC900 的制备中起着至关重要的作用，并且可以重复使用。在 Na-BC900/PDS 体系中，SMX 的降解速率比未改性生物炭（BC900）/PDS 体系高 12 倍。Na-BC900 对 PDS 活化的优异性能归因于其较大的比表面积（SSAs）、增强的石墨化结构和高石墨 N 含量。猝灭和电化学实验、电子顺磁共振（EPR）研究表明，自由基包括 SO、OH、O，非自由基过程由 O 和生物炭介导的电子迁移驱动。自由基和非自由基机制都有助于 SMX 的去除。此外，该催化热解策略被阐明是可扩展的，可以应用于生产多种基于生物质的生物炭催化剂，以修复受污染的水体。
