College of Environmental Science and Engineering, Hunan University, Changsha, 410082, People's Republic of China.
Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, 410082, People's Republic of China.
Environ Sci Pollut Res Int. 2019 Mar;26(8):7614-7626. doi: 10.1007/s11356-019-04173-7. Epub 2019 Jan 21.
The removal of 17β-estradiol (E2) from contaminated water on nanoscale Fe-Mn binary oxide-loaded multiwalled carbon nanotubes (MWCNTs/FMBO) was evaluated in this work. The characterizations of the mesoporous adsorbent were analyzed by using SEM, TEM, VSM, XRD, XPS, and FTIR measurements. The effects of experimental conditions in E2 removal, including stabilizer additional level, adsorption time, initial E2 concentration, solution pH, reaction temperature, and foreign ions, were examined. The maximum monolayer adsorption capacity (q) of MWCNTs/FMBO for E2 in the experiment was 47.25 mg/g as verified by the Langmuir sorption isotherm study. The adsorption process was pH-sensitive with an optimum pH of 7.0. On the kinetics study, the adsorption data could be satisfactorily fitted by the pseudo-second-order kinetics. Thermodynamic parameters indicated that the adsorption process was spontaneous and exothermal. In addition, the foreign ions did not show any noticeable inhibition for E2 removal from the water solution except for PO that was adversely affected for E2 uptake than other anions in a certain concentration. The adsorption capacities of the mesoporous adsorbent remained at 86.16% even after five adsorption-desorption cycles without significant loss of capacity, which demonstrated the stability and reusability for further removal of E2. Moreover, both hydrogen bond and π-π interaction might be the dominating adsorption mechanisms for E2 adsorption onto MWCNTs/FMBO.
本工作评价了纳米级 Fe-Mn 二元氧化物负载多壁碳纳米管（MWCNTs/FMBO）去除受污染水中 17β-雌二醇（E2）的效果。采用 SEM、TEM、VSM、XRD、XPS 和 FTIR 测量对中孔吸附剂的特性进行了分析。考察了 E2 去除实验条件的影响，包括稳定剂添加水平、吸附时间、初始 E2 浓度、溶液 pH 值、反应温度和共存离子。通过 Langmuir 吸附等温线研究验证，MWCNTs/FMBO 对 E2 的最大单层吸附容量（q）为 47.25mg/g。吸附过程对 pH 值敏感，最佳 pH 值为 7.0。在动力学研究中，吸附数据可以通过拟二级动力学很好地拟合。热力学参数表明，吸附过程是自发的和放热的。此外，除 PO 外，共存离子对从水溶液中去除 E2 没有表现出任何明显的抑制作用，在一定浓度下，PO 对 E2 摄取的抑制作用大于其他阴离子。即使在五次吸附-解吸循环后，介孔吸附剂的吸附容量仍保持在 86.16%，没有明显的容量损失，这表明其具有稳定性和可重复使用性，可进一步去除 E2。此外，氢键和π-π相互作用可能是 E2 吸附到 MWCNTs/FMBO 上的主要吸附机制。
