State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
Springside Chestnut Hill Academy, 500 West Willow Grove Avenue, Philadelphia, PA, 19118, USA.
Chemosphere. 2020 Dec;261:127704. doi: 10.1016/j.chemosphere.2020.127704. Epub 2020 Jul 18.
Iron(III)-tetraamidomacrocyclic ligand (Fe(III)-TAML) activators can activate hydrogen peroxide to oxidize many kinds of organic pollutants. In this study, we investigated the degradation of triclosan, a widely used broad-spectrum bactericide, under the treatment of Fe(III)-TAML/HO system at different pH conditions. We also studied the influence of natural organic matter (NOM) on the degradation process. Our results showed that complete removal of triclosan could be obtained within several minutes under the optimal conditions. The degradation of triclosan by Fe(III)-TAML/HO system exhibited strong pH-dependence and the degradation rate increased with the increase in pH level from 7.0 to 10.0. When adding fulvic acid (FA) or humic acid (HA) in the reaction system, the degradation of triclosan could be suppressed slightly, and HA exhibited stronger inhibition than FA. Based on the analysis of reaction intermediates, phenoxyl radical reaction and ring open reaction were involved in the decomposition of triclosan. Significant inhibition of overall toxicity to Photobacterium phosphoreum further confirmed the high efficiency of Fe(III)-TAML/HO system for the removal of antibiotic activities resulting from the parent triclosan molecule and its degradation products.
铁（III）-四酰胺大环配体（Fe（III）-TAML）激活剂可以激活过氧化氢来氧化多种有机污染物。在这项研究中，我们研究了在不同 pH 条件下 Fe（III）-TAML/HO 体系处理下，三氯生（一种广泛使用的广谱杀菌剂）的降解情况。我们还研究了天然有机物（NOM）对降解过程的影响。我们的结果表明，在最佳条件下，三氯生可以在几分钟内完全去除。Fe（III）-TAML/HO 体系降解三氯生的过程强烈依赖于 pH 值，降解速率随着 pH 值从 7.0 增加到 10.0 而增加。当在反应体系中加入富里酸（FA）或腐殖酸（HA）时，三氯生的降解可以被轻微抑制，并且 HA 的抑制作用强于 FA。基于反应中间体的分析，酚氧自由基反应和开环反应参与了三氯生的分解。对发光菌的整体毒性的显著抑制进一步证实了 Fe（III）-TAML/HO 体系对去除母体三氯生分子及其降解产物的抗生素活性的高效性。
