High performance functionalized UiO metal organic frameworks for the efficient and selective adsorption of Pb (II) ions in concentrated multi-ion systems
High performance functionalized UiO metal organic frameworks for the efficient and selective adsorption of Pb (II) ions in concentrated multi-ion systems
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DOI：
10.1016/j.jece.2021.105191
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发表时间：
2021-02-24
影响因子：
7.7
通讯作者：
El-Shall, M. Samy
中科院分区：
文献类型：
--
作者：
Morcos, George S.;Ibrahim, Amr Awad;El-Shall, M. Samy
在这项工作中，我们报告了新的胺官能化的锆基金属有机框架（MOFs）的有效和选择性去除铅（II）在浓缩的多组分重金属离子系统。原始UiO-66和UiO-67 M0 F通过简单的一步合成后修饰用硫脲和脒基硫脲接枝。这是首次将脒基噻吩接枝到MOFs上的报道。通过傅里叶变换红外光谱、X射线衍射和X射线光电子能谱证实接枝成功。一个机制，涉及脱水，电离和协调步骤，提出了接枝和随后的Pb（II）绑定。微孔脒基噻吩修饰的UiO-66和UiO-67 MOFs表现出优异的性能，它们的最大吸附容量分别为246和367 mg.g（-1），以及它们对高浓度多离子溶液中Pb（II）离子的显著选择性。此外，它们的有效去除效率在高范围的Pb（II）浓度（25-250 ppm）下高达95%以上。此外，MOF晶体的结构稳定性在吸附后保持不变，并且MOF完全再生长达四个循环。因此，开发的MOFs可以作为可靠的吸附剂用于工业废水中Pb（II）的去除。
In this work, we report novel amine-functionalized zirconium-based metal organic frameworks (MOFs) for the efficient and selective removal of Pb (II) in concentrated multi-component heavy metal ions systems. Pristine UiO-66 and UiO-67 MOFs were grafted with thiourea and amidinothiourea via a facile one-step post synthetic modification. This is the first report on grafting of amidinothiourea onto MOFs. Successful grafting was confirmed by Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. A mechanism involving dehydration, ionization and coordination steps was proposed for grafting and subsequent Pb (II) binding. The microporous amidinothiourea modified UiO-66 and UiO-67 MOFs demonstrated excellent performance in their high maximum adsorption capacities of 246 and 367 mg.g(-1), respectively, as well as their remarkable selectivity for Pb (II) ions in highly concentrated multi-ion solutions. This is, in addition, to their effective removal efficiencies which reached up to more than 95% at a high range of Pb (II) concentrations (25-250 ppm). Furthermore, the structural stability of the MOF crystals was maintained after adsorption and the MOF was completely regenerated for up to four cycles. The developed MOFs can thus be utilized as reliable adsorbents for Pb (II) removal from industrial wastewater effluents.