State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Environment, Resource, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, PR China; Engineering Research Center of Biochar of Zhejiang Province, Hangzhou 310021, PR China.
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Environment, Resource, Soil and Fertilizers, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, PR China.
J Hazard Mater. 2024 Mar 5;465:133490. doi: 10.1016/j.jhazmat.2024.133490. Epub 2024 Jan 11.
This study indicated that the application of a novel Fe-Mn modified rice straw biochar (Fe/Mn-RS) as soil amendment facilitated the removal of sulfamonomethoxine (SMM) in soil water microcosms, primarily via activating degradation mechanism rather than adsorption. The similar enhancement on SMM removal did not occur using rice straw biochar (RS). Comparison of Fe/Mn-RS with RS showed that Fe/Mn-RS gains new physic-chemical properties such as abundant oxygenated C-centered persistent free radicals (PFRs). In the Fe/Mn-RS microcosms, the degradation contributed 79.5-83.8% of the total SMM removal, which was 1.28-1.70 times higher than that in the RS microcosms. Incubation experiments using sterilized and non-sterilized microcosms further revealed that Fe/Mn-RS triggered both the biodegradation and abiotic degradation of SMM. For abiotic degradation of SMM, the abundant •OH generation, induced by Fe/Mn-RS, was demonstrated to be the major contributor, according to EPR spectroscopy and free radical quenching experiments. Fenton-like bio-reaction occurred in this process where Fe (Ⅲ), Mn (Ⅲ) and Mn (Ⅳ) gained electrons, resulting in oxidative hydroxylation of SMM. This work provides new insights into the impacts of biochar on the fates of antibiotics in soil water and a potential solution for preventing antibiotic residues in agricultural soil becoming a non-point source pollutant.
本研究表明，新型 Fe-Mn 修饰的稻草生物炭（Fe/Mn-RS）作为土壤改良剂的应用促进了土壤水微环境中磺胺甲恶唑（SMM）的去除，主要是通过激活降解机制而不是吸附。使用稻草生物炭（RS）不会产生类似的 SMM 去除增强效果。与 RS 相比，Fe/Mn-RS 获得了新的物理化学性质，如丰富的含氧 C 中心持久自由基（PFRs）。在 Fe/Mn-RS 微环境中，降解贡献了总 SMM 去除的 79.5-83.8%，是 RS 微环境中的 1.28-1.70 倍。使用灭菌和非灭菌微环境进行的孵育实验进一步表明，Fe/Mn-RS 触发了 SMM 的生物降解和非生物降解。对于 SMM 的非生物降解，通过 EPR 光谱和自由基猝灭实验证明，Fe/Mn-RS 诱导的大量 •OH 生成是主要贡献者。在此过程中发生类芬顿生物反应，Fe(Ⅲ)、Mn(Ⅲ)和 Mn(Ⅳ)获得电子，导致 SMM 的氧化羟化。这项工作为生物炭对土壤水中抗生素命运的影响提供了新的见解，并为防止农业土壤中抗生素残留成为非点源污染物提供了一种潜在的解决方案。
