In order to prepare high-performance biochar for application in the treatment of antibiotic wastewater by persulfate oxidation, the feasibility of preparing Fe-N biochar from waste chestnut shells by sequential doping of exogenous iron, nitrogen was investigated. Biochar containing Fe-N structure (Fe₃N-BC) was successfully prepared by using K₂FeO₄ as the iron source and urea as the nitrogen source. It can effectively activate PS and remove 98% of oxytetracycline (OTC) within 20 min. The main mechanism of PS activation by Fe₃N-BC for OTC degradation is a non-radical pathway dominated by ¹O₂ generation and direct electron transfer. The formation of Fe-N structure in biochar changed the electron distribution on the catalyst surface and improved the electron transfer efficiency while inhibiting the leaching of iron ions, verifying the unique role of heteroatoms in iron-based catalysts. The study also identified the degradation intermediates of OTC and suggested possible degradation pathways. Showing that demethylation, deamidation and dehydroxylation are the prior steps for degradation. This study provides a new idea for the preparation of Fe-N structured biochar for OTC degradation.

【摘要】：为制备高性能生物炭应用于过硫酸盐氧化处理抗生素废水,考察了利用外源铁、氮顺序掺杂废栗壳制备铁氮生物炭的可行性。以K ₂ FeO ₄为铁源，尿素为氮源成功制备了含有Fe-N结构的生物炭(Fe _{3 N-BC)。}它可以有效激活 PS，并在 20 分钟内去除 98% 的土霉素 (OTC)。_{Fe 3} N-BC激活PS降解OTC的主要机制是以¹ O ₂为主的非自由基途径产生和直接电子转移。生物炭中Fe-N结构的形成改变了催化剂表面的电子分布，提高了电子转移效率，同时抑制了铁离子的浸出，验证了杂原子在铁基催化剂中的独特作用。该研究还确定了 OTC 的降解中间体，并提出了可能的降解途径。表明去甲基化、脱酰胺化和脱羟基化是降解的先行步骤。该研究为制备可降解OTC的Fe-N结构生物炭提供了新思路。