Pyrite enables persulfate activation for efficient atrazine degradation
Pyrite enables persulfate activation for efficient atrazine degradation
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黄铁矿能够激活过硫酸盐，从而有效降解莠去津
DOI：
10.1016/j.chemosphere.2019.125568
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发表时间：
2020
期刊：
影响因子：
8.8
通讯作者：
Zhang Lizhi
中科院分区：
文献类型：
--
作者：
Wang Xiaobing;Wang Yueyao;Chen Na;Shi Yanbiao;Zhang Lizhi
过硫酸盐（PS）广泛用于环境修复，但其有机污染物的去除性能很大程度上取决于其活化。在这项研究中，我们证明黄铁矿 (FeS2) 比常用的 FeSO4 能够更有效地激活 PS 来降解莠去津。当使用3.0 mM PS和4.2 mM铁盐时，FeS2/PS的莠去津降解效率是FeSO4/PS的1.4倍，而FeS2的PS消耗量仅为FeSO4的53%。 FeS2更好的PS活化性能可能归因于其缓慢且可持续地释放溶解的Fe(II)，抑制·SO4−/·OH和Fe(II)离子之间的猝灭反应，从而产生更多的活性氧用于莠去津降解。更重要的是，FeS2表面结合的Fe(II)可以激活分子氧产生超氧自由基(·O2−)，从而加速Fe(III)/Fe(II)氧化还原循环，进一步促进PS的有效分解。该研究揭示了溶解的Fe(II)和表面结合的Fe(II)在过硫酸盐活化中的作用，并为污染物控制和环境修复提供了一种有前途的非均相过硫酸盐活化剂。
Persulfate (PS) is widely used for environmental remediation, but its organic contaminant removal performance strongly depends on its activation. In this study, we demonstrate that pyrite (FeS2) can more effectively activate PS than the commonly used FeSO4for atrazine degradation. When 3.0 mM of PS and 4.2 mM of iron salts were used, the atrazine degradation efficiency of FeS2/PS was 1.4 times that of FeSO4/PS, while the amount of consumed PS in case of FeS2was only 53% of that by FeSO4. The better PS activation performance of FeS2could be attributed to its slow and sustainable release of dissolved Fe(II), inhibiting the quenching reaction between •SO4−/•OH and Fe(II) ions, and thus producing more reactive oxygen species for the atrazine degradation. More importantly, the surface bound Fe(II) of FeS2could activate molecular oxygen to generate superoxide radical (•O2−), which could further promote the effective decomposition of PS by accelerating the Fe(III)/Fe(II) redox cycle. This study unravels the roles of dissolved Fe(II) and surface bound Fe(II) on the persulfate activation, and provides a promising heterogeneous persulfate activator for pollutant control and environmental remediation.