CNT负载纳米铁阴极电芬顿降解左氧氟沙星  

Degradation of levofloxacin by electro-Fenton with CNT supported nano-iron cathode

作　　者：冯凡 郭波[1] 曹群 金史怡 王瑞麟 陈彩玉 FENG Fan;GUO Bo;CAO Qun;JIN Shi-yi;WANG Rui-lin;CHEN Cai-yu(Department of Environmental Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学环境科学与工程学院,山西太原030024

出　　处：《中国环境科学》2024年第10期5513-5521,共9页China Environmental Science

基　　金：山西省基础研究计划(202403021211220)。

摘　　要：利用浓硫酸对碳纳米管(CNT)进行改性,并以改性CNT(MCNT)上负载铁(MCNT-Fe)作为阴极,构建非均相电芬顿体系,用于去除左氧氟沙星(LFV)的研究.阴极材料的SEM、XPS、XRD和FTIR的表征结果显示:负载铁以纳米Fe_(2)O_(3)形式存在,大多数粒子(>80%)大小在8nm以内;MCNT表面存在多种含氧基团.阴极材料的循环伏安曲线(CV)和阻抗分析(EIS)表明:与CNT和MCNT比较,MCNT-Fe阴极的氧还原活性更大,电子传递能力更强.因而MCNT-Fe阴极的电芬顿法有更高的LFV去除效率.该电芬顿法在优化条件下,pH值3~9,反应240min时LFV去除率可达92.7%~95.7%;线态氧(^(1)O_(2))起主要作用(贡献率达64.6%).此外,MCNT-Fe阴极在多次重复使用中性质稳定,经6次循环使用后的LFV去除率仍可达到89.3%.拓宽的pH值适用范围、稳定的阴极表现以及良好的LFV去除效果非常利于MCNT-Fe阴极的电芬顿法的实际应用,本文提出的^(1)O_(2)可能的形成机制为该法的应用提供了理论依据.Carbon nanotubes(CNT)were modified using concentrated sulfuric acid,and the modified CNTs(MCNT)were employed as the support for iron(MCNT-Fe)to construct a heterogeneous electro-Fenton system with the cathode of MCNT-Fe for the removal of levofloxacin(LFV).Characterization results of the cathode material by SEM,XPS,XRD,and FTIR revealed that the loaded iron existed in the form of nano-Fe_(2)O_(3) with the majority of particles(>80%)being smaller than 8nm,while various oxygen-containing functional groups were found on the surface of MCNT.Analysis of the cyclic voltammetry curves(CV)and impedance spectra(EIS)of the cathode materials indicated that the MCNT-Fe cathode exhibited greater oxygen reduction activity and stronger electron transfer capability than CNT and MCNT.Consequently,the electro-Fenton with the MCNT-Fe cathode demonstrated higher LFV removal efficiency.Under optimized conditions,the LFV removal efficiency could reach 92.7%~95.7%in range of pH 3~9 after 240min reaction.The Singlet oxygen(^(1)O_(2))was identified as the primary reactive oxygen species(contributing to 64.6%).Furthermore,the MCNT-Fe cathode exhibited stable performance during multiple cycles with LFV removal rate of 89.3%after six cycles.The expanded pH range,stable cathode performance,and excellent LFV removal performance make the electro-Fenton method with MCNT-Fe cathode highly suitable for practical application.The proposed mechanism for the formation of ^(1)O_(2) provides theoretical support for its application.

关 键 词：改性阴极 电芬顿 碳纳米管 左氧氟沙星 线态氧 

分 类 号：X703.1[环境科学与工程—环境工程]