Fe_(3)O_(4)/MoS_(2)强化过氧化单硫酸盐活化去除2,4-二氯苯氧乙酸  

Removal of 2,4-dichlorophenoxyacetic acid by Fe_(3)O_(4)/MoS_(2) enhanced PMS activation.

作　　者：方志勇 郭枭杰 周鑫[1] 罗豪鹏 周娟[1] FANG Zhiyong;GUO Xiaojie;ZHOU Xin;LUO Haopeng;ZHOU Juan(College of Environmental Science and Engineering,Donghua University,Shanghai,201620,China)

机构地区：[1]东华大学环境科学与工程学院,上海201620

出　　处：《环境化学》2022年第4期1435-1443,共9页Environmental Chemistry

基　　金：国家重点研发计划项目(2019YFC0408505)资助。

摘　　要：以MoS_(2)为载体,通过水热法合成Fe_(3)O_(4)/MoS_(2)催化剂,采用X射线衍射、透射电子显微镜和X射线光电子能谱分析对材料进行表征,研究了Fe_(3)O_(4)/MoS_(2)/PMS体系中2,4-二氯苯氧基乙酸(2,4-D)的降解效率并探究了其反应机理.结果表明,以Fe_(3)O_(4)、MoS_(2)和Fe_(3)O_(4)/MoS_(2)为催化剂,30 min内2,4-D的去除率分别为31%、20%和89%.表征结果发现,在MoS_(2)的存在下,Fe_(3)O_(4)表面的Fe(Ⅲ)还原为Fe(Ⅱ),Mo(Ⅳ)被氧化为Mo(Ⅵ),Fe_(3)O_(4)和MoS_(2)间的协同作用加强了PMS分解,提高了2,4-D去除效率.自由基淬灭实验表明,·OH、SO_(4)^(-)·、O_(2)·和^(1)O_(2)均参与了2,4-D的降解过程,且^(1)O_(2)的作用比其他活性物质更显著.低浓度Cl^(-)和腐殖酸(HA)对2,4-D的降解没有明显的抑制效果,而HCO-3对Fe_(3)O_(4)/MoS_(2)/PMS体系有明显的抑制作用.此外,催化剂循环实验表明Fe_(3)O_(4)/MoS_(2)在催化反应过程前后保持良好的稳定性.Fe_(3)O_(4)/MoS_(2) catalyst was synthesized by hydrothermal method with MoS_(2) as support.The material was characterized by X-ray diffraction,transmission electron microscopy and X-ray photoelectron spectroscopy analysis.The degradation efficiency and influencing factors of 2,4-dichlorophenoxyacetic acid(2,4-D)in Fe_(3)O_(4)/MoS_(2)/PMS system were studied,and the reaction mechanism was explored.The results showed that when Fe_(3)O_(4),MoS_(2) and Fe_(3)O_(4)/MoS_(2) were used as catalysts,the removal rates of 2,4-D within 30 min were 31%,20% and 89%,respectively.Characterization results showed that in the presence of MoS_(2),Fe(Ⅲ)on the surface of Fe_(3)O_(4) was reduced to Fe(Ⅱ)accompanied by the oxidation of Mo(Ⅳ)to Mo(Ⅵ),and the synergistic effect between Fe_(3)O_(4) and MoS_(2) enhanced PMS decomposition and improved the removal efficiency of 2,4-D.The experiment of radical quenching showed that·OH,SO_(4)^(-)·,O_(2)^(-)·and ^(1)O_(2) were all involved in the degradation process of 2,4-D,and the effect of ^(1)O_(2) was more significant than that of other active substances.Low concentrations of Cl^(-) and humic acid(HA)had no obvious inhibitory effect on the degradation of 2,4-D,while HCO_(3)^(-) had obvious inhibitory effect on Fe_(3)O_(4)/MoS_(2)/PMS system.In addition,XRD and catalyst cycling experiments show that Fe_(3)O_(4)/MoS_(2) maintains good stability before and after the catalytic reaction.

关 键 词：过一硫酸盐 四氧化三铁 二硫化钼 2 4-二氯苯氧基乙酸 

分 类 号：X703[环境科学与工程—环境工程]