National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, College of Resources and Environment, Shandong Agricultural University, Tai'An, 271018, China.
National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, College of Resources and Environment, Shandong Agricultural University, Tai'An, 271018, China.
J Hazard Mater. 2018 Jun 5;351:206-214. doi: 10.1016/j.jhazmat.2018.03.001. Epub 2018 Mar 8.
Due to considerable application of perfluorooctanoic acid (PFOA) and its refractory degradation, the widespread distribution of PFOA has already resulted in its' risks to environment and organisms. However, the intrinsic characteristic of pristine multi-walled carbon nanotubes (MWCNTs) limited their application for removing PFOA from aqueous medium. Therefore, three nano-metals (nano-crystalline iron, copper and zinc) grafted MWCNTs were synthesized and characterized by BET-N, TEM, FTIR, XPS and XRD as well as MWCNTs (as the control treatment) in this study. The results showed that nano metals were well grafted on the surface of MWCNTs. Adsorption were investigated by using radioactive labeled PFOA (C-PFOA) to quantify the trace PFOA. Adsorption kinetics showed the adsorption of PFOA on the metal doped MWCNTs (MDCNTs) was controlled by intra-particle diffusion. Adsorption isotherms showed the sorption amounts on the MDCNTs were higher than the control. This attributed much to the hydrophobic interaction, electrostatic interaction and the formation of the inner sphere complexes. Ionic strength (0-100 mM) and ionic species (Ca) had little effects on the sorption of MDCNTs. PFOA adsorption on MDCNTs strongly depended on pH value in the medium. These results provide an innovative approach for removing trace PFOA from liquid medium.
由于全氟辛酸 (PFOA) 的大量应用及其难降解性，PFOA 的广泛分布已经对环境和生物造成了风险。然而，原始多壁碳纳米管 (MWCNTs) 的固有特性限制了其在从水介质中去除 PFOA 方面的应用。因此，本研究通过 BET-N、TEM、FTIR、XPS 和 XRD 以及 MWCNTs（作为对照处理）合成并表征了三种纳米金属（纳米晶铁、铜和锌）接枝 MWCNTs。结果表明，纳米金属很好地接枝在 MWCNTs 表面。使用放射性标记的 PFOA（C-PFOA）进行吸附研究以定量痕量 PFOA。吸附动力学表明，PFOA 在金属掺杂 MWCNTs（MDCNTs）上的吸附受内扩散控制。吸附等温线表明，MDCNTs 上的吸附量高于对照。这主要归因于疏水相互作用、静电相互作用和内球配合物的形成。离子强度（0-100mM）和离子种类（Ca）对 MDCNTs 的吸附影响不大。MDCNTs 对 PFOA 的吸附强烈依赖于介质中的 pH 值。这些结果为从液体介质中去除痕量 PFOA 提供了一种创新方法。
