非金属原子掺杂石墨烯活化过硫酸盐降解磺胺抗生素废水的过程与机制

As an important emerging organic pollutant in water environment, sulfonamide antibiotics has threatened our aquatic ecology safety. Advanced oxidation processes based on activation of persulfate process is an efficient way to degrade the sulfonamides. But the active methods decided the efficiency of persulfate oxidation. Thus, the active methods of persulfate directly decided sulfonamide antibiotic degradation pathways and play the key role in removal efficiency and aquatic ecology safety. Hence, in this work, nonmetallic atoms-doped (N, P, B) graphene are prepared by different ways, and the induction on persulfate activation and the active mechanism are analyzed firstly. The doping atoms and the doping sites on graphene were optimized. Then sulfonamides degradation performance by persulfate activation using different nonmetallic atoms doping graphene is discussed. The quantitative structure-activity relationships (QSAR) between the kinetic constant of pollutants and the structure of sulfonamides are established. The intermediates in the persulfate activation process are identified and the Gaussian theory calculation is also adopted in comprehensive pathways speculation to illustrate the degradation rules of sulfonamides in the persulfate activation process by graphene. Finally, the toxicity of the intermediates and products are tested to provide reliable basis for the directional selection of safe degradation pathways.

磺胺类抗生素废水排放至水环境中，对我国水生态安全构成威胁。基于过硫酸盐的高级氧化技术，以其高效、经济等优点被视为未来最具潜力的技术之一。然而，过硫酸盐氧化效能的发挥取决于其活化策略的选择。活化策略直接影响目标污染物的降解路径，是制约处理效率和出水安全的关键因素。因此，本课题选择不同非金属原子（N、P和B）掺杂制备石墨烯作为活化剂，考察其对过硫酸盐的活化效能与作用机制，优化最佳活化效能时的掺杂原子种类及掺杂位点。然后，对比不同非金属原子掺杂石墨烯活化过硫酸盐降解磺胺类抗生素的效能；构建污染物降解动力学常数与污染物结构之间的定量构效关系。定性不同非金属原子掺杂石墨烯活化过硫酸盐氧化磺胺类抗生素的中间产物，同时结合理论化学计算，全方位揭示磺胺类抗生素废水在该氧化体系中的降解规律。最后，对降解过程中的中间产物及终产物进行毒性分析，为磺胺类抗生素安全降解途径的定向选择提供可靠方法。

磺胺类抗生素废水排放至水环境中，对我国水生态安全构成威胁。基于过硫酸盐的高级氧化技术，以其高效、经济等优点被视为未来最具潜力的技术之一。然而，过硫酸盐氧化效能的发挥取决于其活化策略的选择。活化策略直接影响目标污染物的降解路径，是制约处理效率和出水安全的关键因素。因此，本课题选择不同非金属原子掺杂制备石墨烯作为活化剂，考察其对过硫酸盐的活化效能与作用机制。明晰了非金属原子对石墨烯结构的改性作用，非金属原子的引入打破了原始石墨烯结构的化学惰性，产生局部电势差，为过硫酸盐活化提供更多的活性位点。同时探究了石墨烯活化过硫酸盐的机理，包括新型单线态氧和电子转移机制，区别于传统自由基主导机理。以磺胺类抗生素为目标污染物，考察了石墨烯活化过硫酸盐体系对其的降解的效能与影响因素。结合理论计算和质谱检测，全方位揭示磺胺类抗生素废水在该氧化体系中的降解规律。