Yu Ruixin, Zhao Jianhui, Zhao Zhiwei, Cui Fuyi
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, PR China.
J Hazard Mater. 2020 May 15;390:121998. doi: 10.1016/j.jhazmat.2019.121998. Epub 2019 Dec 30.
In this paper, copper substituted zinc ferrite (ZCFO) catalyst with rich oxygen vacancies (OVs) was synthesized via a simple one pot sol-gel combustion method, and firstly used for peroxymonosulfate (PMS) activation to degrade a typical antibiotic ciprofloxacin (CIP). Only ∼15 min was required to achieve 96.6% of CIP degradation using ZCFO as the catalyst, and the pseudo-first-order reaction constant was about 95 times higher than that of conventional zinc ferrite (1.90 min vs 0.02 min). ZCFO catalyst showed great stability and reusability based on the successive degradation cycles and could be easily recovered through magnetic separation. Besides, the effects of catalyst loading, PMS concentration, reaction temperature, initial solution pH, coexisting anions and humic acid (HA) on CIP degradation were systematically investigated. Radical quenching tests and electron paramagnetic resonance (EPR) revealed that sulfate radical (SO), hydroxyl radical (OH∙), superoxide radical (O) and singlet oxygen (O) were involved in the ZCFO/PMS system, among which O and O were the dominant reactive oxygen species (ROS). The excellent catalytic activity of ZCFO was ascribed to the dual active sites of Fe and Cu and large amount of OVs after Cu substitution, which was beneficial to generate ROS for CIP removal.
本文通过简单的一锅溶胶 - 凝胶燃烧法合成了具有丰富氧空位（OVs）的铜取代锌铁氧体（ZCFO）催化剂，并首次将其用于过一硫酸盐（PMS）活化以降解典型抗生素环丙沙星（CIP）。以ZCFO为催化剂，仅需约15分钟就能实现96.6%的CIP降解，其准一级反应常数比传统锌铁氧体高约95倍（1.90分钟对0.02分钟）。基于连续的降解循环，ZCFO催化剂表现出良好的稳定性和可重复使用性，并且可以通过磁分离轻松回收。此外，系统研究了催化剂负载量、PMS浓度、反应温度、初始溶液pH值、共存阴离子和腐殖酸（HA）对CIP降解的影响。自由基猝灭试验和电子顺磁共振（EPR）表明，硫酸根自由基（SO）、羟基自由基（OH∙）、超氧自由基（O）和单线态氧（O）参与了ZCFO/PMS体系，其中O和O是主要的活性氧物种（ROS）。ZCFO优异的催化活性归因于Fe和Cu的双活性位点以及Cu取代后大量的氧空位，这有利于产生活性氧以去除CIP。
