研究报告
秦航道,肖榕,吴思展,石维,佘远斌.MnFe2O4磁性纳米棒非均相Fenton催化降解水中四环素的研究[J].环境科学学报,2020,40(11):3913-3921
MnFe2O4磁性纳米棒非均相Fenton催化降解水中四环素的研究
- Heterogeneous Fenton degradation of tetracycline in water catalyzed by magnetic MnFe2O4 nanorods
- 基金项目:贵州省科技计划项目(No.黔科合LH字[2015]7231号)
- 秦航道
- 1. 铜仁学院材料与化学工程学院, 铜仁 554300;2. 浙江工业大学化工学院, 杭州 310014
- 吴思展
- 铜仁学院材料与化学工程学院, 铜仁 554300
- 石维
- 铜仁学院材料与化学工程学院, 铜仁 554300
- 摘要:采用水热合成法成功制备出MnFe2O4磁性纳米棒(s-MnFe2O4),并考察了商品化的Fe3O4、MnFe2O4和合成的s-MnFe2O4纳米棒这3种磁性纳米颗粒作为非均相Fenton催化剂降解水中四环素抗生素的性能.同时,采用X射线衍射(XRD)、透射电镜(TEM)、N2吸附-脱附、振动样品磁强计(VSM)及X射线光电子能谱(XPS)等技术对催化剂的理化性质进行了表征.非均相Fenton催化降解四环素的结果表明,s-MnFe2O4具有最高的催化活性,反应180 min,四环素的去除率可以达到87.6%,TOC的去除率达到47.5%.自由基捕获试验证实了羟基自由基(·OH)是非均相Fenton氧化过程中的主要活性物种.s-MnFe2O4磁性纳米棒的高催化活性归因于其表面拥有较高含量的Mn3+和Fe2+物种,它们的存在能加速界面电子的转移效率,从而促进·OH的生成.合成的s-MnFe2O4催化剂具有良好的稳定性,循环使用6次,四环素的去除率仅从87.6%降低到80.2%,且氧化过程中活性组分的流失很少.
- Abstract:Magnetic MnFe2O4 nanorods (s-MnFe2O4) were successfully prepared by the hydrothermal synthesis. The commercial Fe3O4, MnFe2O4 and the synthesized s-MnFe2O4 were tested as heterogeneous Fenton catalysts in the degradation of tetracycline antibiotic in water. The physical and chemical properties of these catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption-desorption, vibrating sample magnetometer (VSM) and X-ray photoelectron spectroscopy (XPS). The results showed that s-MnFe2O4 exhibited the highest catalytic activity in the degradation of tetracycline. After the reaction of 180 min, the removal rate of tetracycline and TOC were 87.6% and 47.5%, respectively. Based on the quenching experiments, hydroxyl radicals (·OH) were confirmed to be the main active species during the heterogeneous Fenton reaction. The enhanced catalytic activity of s-MnFe2O4 was ascribed to the higher content of Mn3+ and Fe2+, which enhanced the interfacial electron transfer and promoted the generation of ·OH radicals. The stability of s-MnFe2O4 catalyst was confirmed to be fairly good and a slight leaching of active component was observed.