CoFe_(2)O_(4)/MnO_(2)活化过一硫酸盐降解盐酸四环素的研究

Degradation of tetracycline hydrochloride by CoFe_(2)O_(4)/MnO_(2)activated permonosulfate

针对四环素类抗生素污染物在水中不断累积,对人体健康和生态环境造成严重危害这一问题,本研究制备了CoFe_(2)O_(4)/MnO_(2)新型复合材料,并将其作为高效过一硫酸盐(PMS)活化剂,用于降解水体中的盐酸四环素(TCH)。降解结果表明CoFe_(2)O_(4)/MnO_(2)-PMS体系具有突出的TCH去除效率,反应40 min后,去除率可达92.7%,远高于单一催化剂-PMS体系。影响因素实验结果显示,CoFe_(2)O_(4)/MnO_(2)-PMS降解体系具有广泛的pH适用性,并且在各种阴离子的存在下仍能保持较高的降解活性。此外,CoFe_(2)O_(4)/MnO_(2)-PMS降解体系具有良好的稳定性和可重复利用性,在5次循环后仍保持较高的催化活性和TCH降解率。机理分析表明CoFe_(2)O_(4)/MnO_(2)复合材料在催化PMS降解TCH的过程中,存在Co^(2+)/Co^(3+)、Fe^(3+)/Fe^(2+)和Mn^(3+)/Mn^(4+)的价态循环并参与电子转移过程,从而使得活化过程中SO_(4)^(-)·和·OH被充分释放,并通过一系列典型的链式反应高效降解TCH。

To address the issue that tetracycline antibiotic pollutants are accumulating in water and causing serious harm to human health and the ecological environment,this study prepared a novel composite material of CoFe_(2)O_(4)/MnO_(2)and used it as a highly efficient permonosulfate(PMS)activator for the degradation of tetracycline hydrochloride(TCH)in the water body.The degradation results showed that the CoFe_(2)O_(4)/MnO_(2)-PMS system had outstanding TCH removal efficiency,which could reach 92.7%after 40 min of reaction,much higher than that of the single catalyst-PMS system.The results of the influencing factor experiments showed that the CoFe_(2)O_(4)/MnO_(2)-PMS degradation system had a wide range of pH suitability and a stable degradation activity in the presence of various anions.In addition,the CoFe_(2)O_(4)/MnO_(2)-PMS degradation system had good stability and reusability,showing high catalytic activity and TCH degradation rate after 5 cycles.Mechanistic analysis showed that the valence cycles of Co^(2+)/Co^(3+),Fe^(3+)/Fe^(2+)and Mn^(3+)/Mn^(4+)existed in the CoFe_(2)O_(4)/MnO_(2)composites to participate in the electron transfer process during the catalytic PMS degradation of TCH,leading to the full release of SO_(4)^(-)·and·OH during the activation process and the effective degradation of TCH through a series of typical chain reactions.