Li Wenpeng, Wang Qingping, Jin Xiaoying, Khan Nasreen Islam, Owens Gary, Chen Zuliang
Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou, 350007, Fujian Province, China.
Fujian Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Fujian Normal University, Fuzhou, 350007, Fujian Province, China.
J Environ Manage. 2021 Jun 1;287:112280. doi: 10.1016/j.jenvman.2021.112280. Epub 2021 Mar 8.
Wastewater generated during mining remains a significant source of antimony pollution, because techniques to quickly and efficiently remove antimony from wastewater do not exist. In this study, zeolitic imidazolate framework-8 (ZIF-8), a specific type of Metal Organic Frameworks (MOFs), was successfully used to remove trace levels (1 mg L) of Sb(V) with a high removal efficiency when the ZIF-8 dose was 0.5 g L. Scanning electron microscopy-X-ray energy dispersive spectrometry (SEM-EDS) indicated that Sb(V) was adsorbed onto the ZIF-8surface. The powder X-ray diffraction (XRD) pattern of ZIF-8 before and after adsorption of Sb(V) indicated that ZIF-8 was successfully synthesized, and remained structurally stable after Sb(V) was adsorbed. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) both suggested complexation of zinc on ZIF-8 with Sb(V), where removal of Sb(V) by ZIF-8 followed the Langmuir adsorption isotherm with pseudo second-order kinetics. Thus, a possible removal mechanism was proposed which involved Sb(V) complexing with the zinc hydroxyl groups on ZIF-8 (Zn-OH-Sb). Practically, ZIF-8, could remove 78.6% of Sb(V) from a mining wastewater containing 20 μg L Sb(V). Furthermore, ZIF-8 could be remain active after repeated uses and could still remove and 42.3% of Sb(V) from wastewater containing 1 mg L) Sb(V) even when the ZIF-8 was reused five time. This indicated that ZIF-8 had potential for practical removal of Sb(V) from mining wastewaters.
采矿过程中产生的废水仍然是锑污染的一个重要来源，因为目前不存在能够快速、高效地从废水中去除锑的技术。在本研究中，一种特定类型的金属有机框架材料——沸石咪唑酯骨架结构材料-8（ZIF-8），当ZIF-8投加量为0.5 g/L时，被成功用于高效去除痕量水平（1 mg/L）的Sb(V)。扫描电子显微镜-能量色散X射线光谱仪（SEM-EDS）分析表明，Sb(V)被吸附到ZIF-8表面。Sb(V)吸附前后ZIF-8的粉末X射线衍射（XRD）图谱表明，ZIF-8成功合成，且在吸附Sb(V)后结构保持稳定。傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XPS）均表明ZIF-8上的锌与Sb(V)发生了络合作用，ZIF-8对Sb(V)的去除遵循朗缪尔吸附等温线和准二级动力学。因此，提出了一种可能的去除机制，即Sb(V)与ZIF-8上的锌羟基（Zn-OH-Sb）发生络合。实际上，ZIF-8能够从含20 μg/L Sb(V)的采矿废水中去除78.6%的Sb(V)。此外，ZIF-8重复使用后仍具有活性，即使重复使用五次，仍能从含1 mg/L Sb(V)的废水中去除42.3%的Sb(V)。这表明ZIF-8在实际去除采矿废水中的Sb(V)方面具有潜力。
