Well-dispersed TiO2 nanoparticles anchored on Fe3O4 magnetic nanosheets for efficient arsenic removal
Well-dispersed TiO2 nanoparticles anchored on Fe3O4 magnetic nanosheets for efficient arsenic removal
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分散良好的 TiO2 纳米颗粒锚定在 Fe3O4 磁性纳米片上，可有效去除砷
DOI：
10.1016/j.jenvman.2019.02.037
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发表时间：
2019-05-01
影响因子：
8.7
通讯作者：
Liu, Qinglin
中科院分区：
文献类型：
--
作者：
Deng, Min;Wu, Xiaodong;Liu, Qinglin
磁性铁钛二元氧化物作为砷污染物的有效吸附剂是一个挑战，主要是因为它们的块体结构和团聚效应。本文采用无定形-晶化转变和H2-还原的方法合成了一种新型均匀的片状磁性Fe3O4@TiO2，并将其分散在Fe 3 O 4片上，粒径约为8 nm。制备的Fe3O4@TiO2片状纳米复合材料具有89.4 m2 g-1的高比表面积和20.0 emu g-1的有效磁化率，显著提高了亚砷酸盐的光催化氧化性能和对砷的吸附去除能力。吸附实验结果表明，在紫外光辅助下，As（V）和As（III）的吸附容量分别为36.36和30.96 mg g（-1），As（V）和As（III）的残留浓度均低于10 μ g L-1的严格限值。吸附平衡几乎在45分钟内达到。此外，吸附剂表现出良好的稳定性，在较宽的pH值范围为3-9，并仍然保持很大的去除效率后，5次再生循环。除硅酸盐和磷酸盐外，常见共存离子对除砷过程的抑制作用极弱，表明所研制的具有独特纳米结构的磁性Fe3O4@TiO2片有望成为一种高效的除砷吸附剂。
Magnetic iron-titanium binary oxide as an effective adsorbent for arsenic contaminant is a challenge primarily because of their bulk structure and agglomeration effect. Herein, a novel and uniform sandwich-like magnetic Fe3O4@TiO2 sheets were synthesized by utilizing a facile strategy involving amorphous-to-crystalline transformation and reduction in H-2, to achieve dispersed anatase TiO2 nanoparticles with a small size of similar to 8 nm anchored on Fe3O4 sheets. The resultant Fe3O4@TiO2 sheets nanocomposite possessing a high specific surface area of similar to 89.4 m(2) g(-1) and available magnetic susceptibility of similar to 20.0 emu g(-1), significantly enhanced the photo catalytic oxidation property of arsenite and considerable adsorption capability for arsenic removal. The adsorption capacities of As(V) and As(III) with UV-assisted from adsorption experimental results were 36.36 and 30.96 mg g(-1), respectively, while the residual concentrations for both As(V) and As(III) were lower than the strict limit of 10 mu g L-1. Adsorption equilibriums were almost reached within 45 min. In addition, the adsorbent exhibited excellent stability over a broad pH range of 3-9 and still maintained great removal efficiency after five time regeneration cycles. Furthermore, except for silicate and phosphate, the extremely weak inhibiting influences of common co-existing ions in arsenic removal process, demonstrated that the developed magnetic Fe3O4@TiO2 sheets with unique nanostructure could be a promising efficient adsorbent for arsenic removal.