磁性纳米CeO2/Fe3O4非均相Fenton反应催化降解氧氟沙星

为了提高Fe₃O₄的催化活性, 制备了磁性CeO₂/Fe₃O₄复合纳米粒子, 构成非均相Fenton反应体系, 催化降解水环境中的氧氟沙星抗生素。研究了CeO₂含量、H₂O₂浓度、pH等因素对CeO₂/Fe₃O₄非均相催化活性的影响, 并通过溶出铁离子测定、动力学拟合等方式对反应机理进行探究。结果表明, CeO₂/Fe₃O₄较Fe₃O₄具有更强的催化活性, 氧氟沙星的降解率随CeO₂含量、H₂O₂浓度和溶液酸度的增加而提高, 当H₂O₂浓度为100 mmol/L 以及pH为3时, CeO₂/Fe₃O₄(摩尔比=0.780)-H₂O₂体系催化降解氧氟沙星的效果最佳。CeO₂/Fe₃O₄体系催化降解氧氟沙星反应遵循一级反应动力学方程, 反应机理主要为催化剂表面的催化反应, 同时CeO₂产生氧空位的电子转移对Fe₃O₄的催化反应起到协同强化的作用。

Heterogeneous Fenton Reaction for Degradation of Ofloxacin with Magnetic CeO2/Fe3O4

CeO₂/Fe₃O₄ magnetic nanoparticles were prepared for promoting the catalytic activity of Fe₃O₄, which is applied as the catalyst of heterogeneous Fenton reaction system for the degradation of ofloxacin. Several factors that affected the degradation efficiency of the system such as CeO₂ content, H₂O₂ concentration and pH were investigated. The mechanism of catalytic degradation was also explored via the measurement of iron ion and kinetics fitting. The results show that the catalytic activity of CeO₂/Fe₃O₄ is better than that of Fe₃O₄. The degradation efficiency of ofloxacin increases with the addition of CeO₂ content, H₂O₂ concentration or solution acidity increase. The degradation effect of ofloxacin is the best for CeO₂/Fe₃O₄(molar roction=0.780)-H₂O₂ catalytic system when H₂O₂ concentration is 100 mmol/L and pH is 3, which accords first order kinetics model. The catalytic ability of CeO₂/Fe₃O₄ is strengthened through surface catalytic reaction and electronic transfer of oxygen vacancies of CeO₂ during catalytic reaction.