Enhanced ferrate(VI) oxidation of micropollutants in water by carbonaceous materials: Elucidating surface functionality
Enhanced ferrate(VI) oxidation of micropollutants in water by carbonaceous materials: Elucidating surface functionality
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DOI：
10.1016/j.cej.2020.125607
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发表时间：
2020-10
影响因子：
15.1
通讯作者：
Bao Pan;Mingbao Feng;T. McDonald;K. Manoli;Chuanyi Wang;Ching-Hua Huang;V. Sharma
中科院分区：
文献类型：
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作者：
Bao Pan;Mingbao Feng;T. McDonald;K. Manoli;Chuanyi Wang;Ching-Hua Huang;V. Sharma
无金属碳质材料在催化去除水中环境污染物方面具有前所未有的性能，越来越受到世界各国的关注。然而，高铁酸盐（VI） （FeVIO42−）是一种新兴的绿色水处理剂，其表面官能依赖性的催化效果和活化机制在很大程度上仍然未知。在这里，我们研究了不同的碳质材料（即碳氢化合物、氧化石墨烯（GO）、还原氧化石墨烯、石墨和富勒烯）是否可以激活FeVIO42 -，并增强其在温和碱性条件下快速氧化多种微污染物（即卡马西平（CBZ）、双氯芬酸、磺胺甲恶唑、磺胺二甲氧嘧啶、甲氧苄啶、氟喹、阿替洛尔和咖啡因）的有效性。例如，在pH为9.0时，在反应体系中加入碳氢化合物或氧化石墨烯，对CBZ的降解效果显著，而对其他三种碳质材料的降解效果不显著。微污染物的种类不同，增强程度也不同。傅里叶变换红外光谱（FTIR）技术结合化学探针（即甲基苯基亚砜）测试证明了烃类表面c双键do基团与FeVIO42−的化学相互作用，其中产生了高价铁氧中间体（即FeIV/FeV）作为氧化物质，以增强修复。此外，在连续五次催化运行中可以看到这种增强，这表明烃类具有高可回收性，可以通过FeVIO42−氧化微污染物。这些发现表明，FeVIO42−的非均相碳质活化有望在轻度碱性反应条件下推进水修复。
Metal-free carbonaceous materials have increasingly attracted worldwide attention owing to their unprecedented properties in catalytic elimination of environmental pollutants in water. Nevertheless, the surface functionality-dependent catalytic efficacy and activation mechanism for ferrate(VI) (FeVIO42−), an emerging green water-treatment agent, have remained largely unknown. Here we have examined if different carbonaceous materials (i.e., hydrochar, graphene oxide (GO), reduced graphene oxide, graphite, and fullerene) can activate FeVIO42−and enhance its effectiveness for rapid oxidation of a wide range of micropollutants (i.e., carbamazepine (CBZ), diclofenac, sulfamethoxazole, sulfadimethoxine, trimethoprim, flumequine, atenolol, and caffeine) under mild alkaline conditions. For example, the addition of hydrochar or GO into the reaction system, at pH 9.0, achieved remarkable enhancement of degradation of CBZ as compared to insignificant effect observed for three other carbonaceous materials. The magnitude of enhancement varied with the moieties of micropollutants. The Fourier-transform infrared spectroscopy (FTIR) technique in conjunction with the chemical probe (i.e., methyl phenyl sulfoxide) tests demonstrated chemical interactions of surface Cdouble bondO groups of hydrochar with FeVIO42−, of which high-valent iron-oxo intermediates (i.e., FeIV/FeV) were generated as the oxidizing species for enhanced remediation. Additionally, this enhancement was seen in five successive catalytic runs, indicating high recyclability of hydrochar to oxidize micropollutants by FeVIO42−. These findings suggest that heterogeneous carbonaceous activation of FeVIO42−holds promise for advancing water remediation under mild alkaline reaction conditions.