Dual-functional sites for synergistic adsorption of Cr(VI) and Sb(V) by polyaniline-TiO2 hydrate: Adsorption behaviors, sites and mechanisms
Dual-functional sites for synergistic adsorption of Cr(VI) and Sb(V) by polyaniline-TiO2 hydrate: Adsorption behaviors, sites and mechanisms
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DOI：
10.1007/s11783-022-1526-7
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发表时间：
2021-12
影响因子：
6.4
通讯作者：
Ning Wang;Jiangtao Feng;Wei Yan;Luo-hong Zhang;Yonghong Liu;Ruihua Mu
中科院分区：
文献类型：
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作者：
Ning Wang;Jiangtao Feng;Wei Yan;Luo-hong Zhang;Yonghong Liu;Ruihua Mu
铬（Cr）和锑（Sb）由于其生物蓄积性、高流动性和强毒性，从水生环境中去除铬（Cr）和锑（Sb）至关重要。本文设计并成功合成了一种由Ti(OH)n(4−n)+和聚苯胺（PANI）组成的复合吸附剂，用于吸附Cr（VI）和Sb(V)。合成的PANI/ tio2复合材料对Cr（VI）和Sb(V)具有良好的吸附能力（Cr（VI）为394.43 mg/g, Sb(V)为48.54 mg/g），具有广泛的pH适用性和显著的可重复使用性。Cr（VI）氧阴离子的吸附主要包括静电吸引、氢键和阴离子π相互作用。通过x射线光电子能谱和红外光谱分析，发现其吸附位点为羟基、氨基/亚胺基和苯环。Sb(V)主要通过氢键吸附和表面络合形成Ti-O-Sb配合物。双体系中Cr- o -Sb的形成证明了Cr（VI）和Sb(V)的协同吸附。更重要的是，由于不同的吸附位置，双体系对Cr（VI）和Sb(V)的吸附是独立发生的，并在一定程度上增强。结果表明，聚苯胺/ tio2具有可获得性、适用性广、可重复利用性好等优点，在实际废水处理中去除Cr（VI）和Sb(V)具有广阔的应用前景。
Removal of chromium (Cr) and antimony (Sb) from aquatic environments is crucial due to their bioaccumulation, high mobility and strong toxicity. In this work, a composite adsorbent consisting of Ti(OH)n(4−n)+and polyaniline (PANI) was designed and successfully synthesized by a simple and eco-friendly method for the uptake of Cr(VI) and Sb(V). The synthetic PANI/TiO2composites exhibited excellent adsorption capacities for Cr(VI) and Sb(V) (394.43 mg/g for Cr(VI) and 48.54 mg/g for Sb(V)), wide pH applicability and remarkable reusability. The adsorption of Cr(VI) oxyanions mainly involved electrostatic attraction, hydrogen bonding and anion-πinteractions. Based on X-ray photoelectron spectroscopy and FT-IR analysis, the adsorption sites were shown to be hydroxyl groups, amino/imino groups and benzene rings. Sb(V) was adsorbed mainly through hydrogen bonds and surface complexation to form Ti-O-Sb complexes. The formation of Cr-O-Sb in the dual system demonstrated the synergistic adsorption of Cr(VI) and Sb(V). More importantly, because of the different adsorption sites, the adsorption of Cr(VI) and Sb(V) occurred independently and was enhanced to some extent in the dual system. The results suggested that PANI/TiO2is a promising prospect for practical wastewater treatment in the removal of Cr(VI) and Sb(V) from wastewater owing to its availability, wide applicability and great reusability.