磁性纳米Fe_(3)O_(4)活化过一硫酸盐降解三氯生性能

Degradation of Triclosan in Water by Magnetic Nanoscale Fe_(3)O_(4) Activated Peroxymonosulfate

采用高级氧化技术磁性纳米Fe_(3)O_(4)活化过一硫酸盐(Fe_(3)O_(4)/PMS)降解水中三氯生(TCS),探讨了Fe_(3)O_(4)投加量、PMS浓度、初始p H值、共存阴离子(Cl^(-)、NO_(3)^(-)、CO_(3)^(2-))和腐殖酸(HA)对TCS降解效果的影响,并对催化剂Fe_(3)O_(4)的稳定性和重复利用进行了考察。结果表明:Fe_(3)O_(4)/PMS会产生硫酸根自由基(SO_(4)^(-)·)降解水中TCS;适量增加Fe_(3)O_(4)投加量、提供适宜的PMS浓度可提高TCS降解率;酸性条件有利于TCS的降解;Cl^(-)和CO_(3)^(2-)对TCS降解具有较小的抑制作用,NO_(3)^(-)对TCS降解具有较小的促进作用;HA的存在对TCS降解有明显的抑制作用。实际水体中TCS降解效果受到碱度和有机质的抑制。XPS光谱分析结果表明,Fe_(3)O_(4)/PMS体系中Fe(Ⅱ)主要参与了激活PMS降解TCS过程。自由基鉴别结果显示,体系中SO_(4)^(-)·和羟基自由基(·OH)同时存在,其中SO_(4)^(-)·为参与反应的主要自由基。

The advanced oxidation process (AOPs) of magnetic nanoscale Fe_(3)O_(4)activated peroxymonosulfate (Fe_(3)O_(4)/PMS) was employed to degrade triclosan (TCS) in water.Effects of Fe_(3)O_(4)dosage,PMS concentration,initial pH value,coexisting anions (Cl^(-),NO_(3)^(-),CO_(3)^(2-)) and humic acid(HA) on TCS degradation were investigated,and stability and recyclability of catalyst Fe_(3)O_(4)were also explored.The results showed that,Fe_(3)O_(4)/PMS could generate SO_(4)^(-)·to decompose TCS in water.Higher Fe_(3)O_(4)dosage and appropriate PMS concentration could increase the TCS degradation rate.Acidic condition was conducive to TCS degradation.Anions of Cl^(-) and CO_(3)^(2-)had little inhibitory effect on TCS degradation,while NO_(3)^(-)had slight promoting effect on TCS degradation.The degradation of TCS was obviously inhibited by the HA.The degradation performance of TCS in actual water was inhibited by alkalinity and organic matter.X-ray photoelectron spectroscopy (XPS) analysis showed that Fe^(2+)was mainly involved in the activation of PMS to degrade TCS in Fe_(3)O_(4)/PMS system.Identification test of free radicals revealed that SO_(4)^(-)·and·OH coexisted in the system,and SO_(4)^(-)·was the dominant radical in the reaction.