Abstract：
Currently, there is a lack of advanced nanotechnology designed to efficiently remove antimony (Sb) from contaminated water systems. Sb most commonly appears as antimonite (Sb(III)) or as the anion antimonate (Sb(V)). Sb(III) is approximately ten times more toxic than Sb(V), and Sb(III) is also harder to eliminate because of its motility and charge neutrality. The work presented here developed an electrochemical filtration technology for the direct elimination of Sb(III) from contaminated water. The primary components of the filtration system were an electroactive carbon nanotube (CNT) membrane that were functionalized with the Sb-specific UiO-66(Zr), an metal-organic framework. In an electric field, the UiO-66(Zr)/CNT nanohybrid filter enabled in situ transformation of Sb(III) to less harmful Sb(V). The Sb(V) was then effectively adsorbed by the UiO-66(Zr). The removal efficiency (90.5%) and rate constant (k1 = 0.0272 min-1) toward Sb(III) removal was 1.3 and 1.4 times greater than that of CNT filter. The abundance of available adsorption sites of the nanohybrid filter, flow-through construction, and electrochemical activity combined to rapidly remove Sb(III) from water. The underlying functioning of the nanohybrid filter was determined with a series of process experiments and structural characterizations. The filter was effective over a broad range of pH values and in a variety of complex aqueous environments. Once loaded with Sb, the UiO-66(Zr)/CNT filter could be washed with a dilute NaOH solution to efficiently refresh its activity. The results of this work offer a direct, efficient strategy that integrates nanotechnology, electrochemistry, and membrane separation to remove antimony and potentially other heavy metals from contaminated water.
摘要：
目前,缺乏先进的纳米技术，旨在有效地从污染的水系统中去除锑（Sb）。Sb最常见的表现为锑酸盐（Sb（III））或阴离子锑酸盐（Sb（V））。Sb（III）的毒性大约是Sb（V）的十倍，和Sb（III）也很难消除，因为它的运动性和电荷中性。本文介绍的工作开发了一种电化学过滤技术，可直接从污染水中消除Sb（III）。过滤系统的主要组件是电活性碳纳米管（CNT）膜，该膜被Sb特异性UiO-66（Zr）功能化，有机金属框架。在电场中,UiO-66（Zr）/CNT纳米混合过滤器使Sb（III）原位转化为危害较小的Sb（V）。然后Sb(V)被UiO-66(Zr)有效地吸附。对Sb（III）的去除效率（90.5％）和速率常数（k1=0.0272min-1）是CNT过滤器的1.3和1.4倍。过滤器丰富的可用吸附位点，流通施工，和电化学活性相结合，从水中快速去除Sb（III）。通过一系列过程实验和结构表征来确定纳米混合过滤器的基本功能。该过滤器在广泛的pH值范围内以及在各种复杂的水性环境中都是有效的。一旦装载了Sb，UiO-66(Zr)/CNT过滤器可以用稀NaOH溶液洗涤以有效地更新其活性。这项工作的结果提供了一个直接的，集成纳米技术的有效战略，电化学,和膜分离，以从污染水中去除锑和潜在的其他重金属。
