紫外光辅助MnFe_(2)O_(4)@活性炭活化过硫酸盐降解盐酸四环素

UV⁃assisted degradation of tetracycline hydrochloride by MnFe_(2)O_(4)@activated carbon activated persulfate

通过水浴-逆共沉淀法制备磁性催化剂MnFe_(2)O_(4)@AC(MFA),并对其结构和磁性进行了系统表征。结果显示,MnFe_(2)O_(4)纳米颗粒包覆在活性炭(AC)表面,构成了多级孔结构。MFA较AC基体材料的比表面积有所下降,但仍高达176 m^(2)·g^(-1),平均孔径为8.49 nm。MFA的比磁化强度高达38.92 emu·g^(-1),可利用外磁场实现高效固液分离。以MFA为催化剂,在紫外光辅助下活化过硫酸氢钾(PMS)降解盐酸四环素(TC)。研究表明,在紫外光辐照下MFA/PMS体系对TC降解率能够达到97.70%,是无紫外光照射体系的1.2倍;共存阴离子、药剂制度、TC初始质量浓度等因素对系统的催化性能具有显著影响。循环5次之后,降解率仍可达到82.76%。自由基猝灭实验表明,超氧自由基(·O_(2)^(-))和单线态氧(^(1)O_(2))是紫外光辅助MFA/PMS高级氧化体系中的主要活性氧。机理分析表明,MFA的高吸附性为催化降解提供了良好的基础,紫外光辐照和MFA/PMS高级氧化体系的协同效应可显著提升活性基团的生成效率,从而促进了有机分子的降解。

The magnetic catalyst MnFe_(2)O_(4)@AC(MFA)was synthesized using a water bath⁃inverse co⁃precipitation method and was systematically characterized to assess its structural and magnetic properties.The results indicated that MnFe_(2)O_(4) nanoparticles were successfully encapsulated on the surface of activated carbon(AC),resulting in a multistage pore structure.Although the specific surface area of MFA decreased compared to that of the AC base material,it remained high at 176 m^(2)·g^(-1),with an average pore size of 8.49 nm.The specific magnetization intensity of MFA reached 38.92 emu·g^(-1),enabling high⁃efficiency solid⁃liquid separation when subjected to an external magnetic field.Tetracycline hydrochloride(TC)was degraded using activated peroxymonosulfate(PMS)with UV⁃assisted activation,employing MFA as a catalyst.The degradation rate of TC in the MFA/PMS system under UV irra⁃diation achieved 97.70%,which was 1.2 times that of the system without UV irradiation.The presence of coexisting anions,the pharmaceutical matrix,and the initial mass concentration of TC significantly influenced the catalytic per⁃formance of the system.Notably,the degradation rate remained at 82.76%after five cycles.Free radical burst exper⁃iments revealed that superoxide radicals(·O_(2)^(-))and monoclinic oxygen(^(1)O_(2))were the primary reactive oxygen spe⁃cies in the UV⁃assisted MFA/PMS advanced oxidation system.Mechanistic analysis indicated that the high adsorp⁃tion capacity of MFA provided a solid foundation for catalytic degradation,and the synergistic effect of UV irradia⁃tion with the MFA/PMS advanced oxidation system significantly enhanced the generation efficiency of reactive spe⁃cies,thereby facilitating the degradation of organic molecules.