全固态Z型异质结耦合过硫酸盐吸附-光催化氧化去除水中微量抗生素的机制研究

Antibiotics in livestock/poultry wastewater from intensive farming areas have posed serious threats to the nearby water environment and aquatic organisms. In recent years, visible light activated persulfate is a highly promising advanced oxidation technology and is expected to achieve efficient mineralization of residual antibiotics and their metabolites in culture tail water. However, there are few reports concerning about the removal rules of antibiotics in this system, and the relevant process and mechanism are still not clear. This study intends to prepare Bi-based/g-C3N4 Z-scheme heterojunction photocatalysts for persulfate activation and to construct a Fenton-like system. The removal efficiency and key factors of antibiotics were investigated in details by batch and dynamic simulation experiments and the essential functions of each component in the combined system were also deeply discussed. The possible persulfate activation mechanism coupled with visible light and photocatalyst was elucidated by an in situ EPR and photo-electrochemical test. Besides, the correspondent degradation pathways of antibiotics were proposed based on above-mentioned results. This work is conducive to develop a new method for the advanced treatment of antibiotics in water by the technology of photo-assisted persulfate activation and to reveal its intrinsic mechanism, adsorption-catalytic oxidation process and migration pathways of micro-antibiotics, which could provide scientific basis and technical support for residual antibiotics removal in tail water from livestock/poultry wastewater.

集约化养殖畜禽废水中抗生素对附近水环境和水生生物造成严重危害。可见光活化过硫酸盐技术是一种近年兴起极具潜力的高级氧化技术，可望实现养殖尾水中残留抗生素及其代谢产物的高效矿化，然而目前对该体系抗生素去除规律较为缺乏，且降解过程和机理尚不明确。本研究拟采用价格低廉Bi基/g-C3N4 Z型异质结为光催化剂，辅以过硫酸盐活化构建类光芬顿系统实现畜禽尾水中抗生素的快速降解。通过批次实验和动态模拟来考察去除抗生素效能和关键影响因素，解析耦合体系中各组分在抗生素降解过程中主要作用。利用原位EPR和光电化学分析阐明过硫酸盐活化主要机理，深入分析抗生素降解中间产物并结合模拟计算，深究其降解路径。本项目的开展有助于研发光辅助过硫酸盐活化深度处理水中抗生素的新方法，并揭示其活化机制、微量抗生素的吸附-催化氧化过程及降解路径，为畜禽养殖尾水中残留抗生素污染去除提供科学依据和技术支撑。

集约化养殖畜禽废水中以抗生素为代表的有机污染物可对附近水环境和水生生物造成严重危害。通过耦合可见光催化与过硫酸盐激活技术对该类废水的净化颇具潜能。本项目中，选取价廉易得、可规模化的g-C3N4基、Bi基以及它们组建的异质结材料作为氧化剂的激活剂，系统考察了耦合系统对典型抗生素和其它新型污染物的去除效能、矿化程度、产物演变和协同机制。提出针对不同系统的选择性、广谱性、环境耐受性等差异应对策略。基于构建系统的稳定性、应用成本和实际应用潜能进行深层次探究。同时结合原位EPR、光电化学分析和理论计算深度剖析污染物去除演变规律和系统催化性能提升的内在机理。其中为提升对活性位点利用的优化，研发出原子级金属位点的高效利用新方式。此外，基于污染物本身具有多特性，提出“以废治废、多污染同步去除”新策略；同时结合污水系统中离子共存较为普遍，设计针对型可有效利用共存离子的新系统，同时可有效避免消毒副产品的产生，提升对抗生素的脱毒和深度去除性能。基于此提出新的可实用性光辅助过硫酸盐激活和类芬顿新技术，为后续该类污废水的快速脱污提供理论依据与技术支撑。