Mo Chen, Faheem Muhammad, Aziz Saba, Jian Song, Xue Wang, Yuyang Tian, Shuang Ding, Guangshan Zhu
Key Laboratory of Polyoxometalate Science of the Ministry of Education, Faculty of Chemistry, Northeast Normal University Changchun 130024 P. R. China
Institute for Interdisciplinary Biomass Functional Materials Studies, Jilin Engineering Normal University Changchun 130052 P. R. China
RSC Adv. 2020 Jul 14;10(44):26335-26341. doi: 10.1039/d0ra04222f. eCollection 2020 Jul 9.
Environmental pollution is an important issue in sustainable human development. People give great importance to environmental protection, especially with regards to increasingly scarce water resources. Water pollution is becoming more and more serious due to the existence of organic micropollutants. As a platform with good stability, porous aromatic frameworks (PAFs) have been widely studied. Because of their high surface area and thermal stability, they are considered to be a good sewage treatment agent. However, the aromatic nature of PAFs makes their skeletons mostly hydrophobic. This characteristic of PAFs seriously affects their diffusion rate in water as an adsorbent, resulting in a low adsorption rate. In this work, we synthesized a series of hydroxyl functionalized porous aromatic frameworks (PAF-80, PAF-81, and PAF-82) the Sonogashira-Hagihara cross-coupling reaction, which created polar motifs on the hydrophobic surfaces, and carried out adsorption tests on typical organic micropollutants in water such as bisphenol A (BPA), 2-naphthol (2-NO) and -chloroxylenol (PCMX). Among the three PAFs, PAF-82 exhibited the highest BET surface area, polar active sites, and a high degree of conjugation, which led to the best adsorption performance compared to that of PAF-80 and PAF-81. The Langmuir adsorption capacity of PAF-82 for BPA, 2-NO, and PCMX is 689 mg g, 431 mg g, and 480 mg g, respectively, which surpasses most previously reported adsorbents. In addition, after 5 cycles of regeneration, it still maintained a high removal rate for pollutants. The obtained results reveal that micropollutant adsorption in water is not controlled by a single factor, but is the result of a synergy of multiple factors, including specific surface area, polar functional groups, pore size distribution, and skeleton conjugation. Our study has revealed the great potential of hydroxyl PAFs for efficient adsorption of organic micropollutants in water.
环境污染是人类可持续发展中的一个重要问题。人们高度重视环境保护，尤其是对于日益稀缺的水资源。由于有机微污染物的存在，水污染正变得越来越严重。作为一种具有良好稳定性的平台，多孔芳香框架（PAFs）已得到广泛研究。因其高比表面积和热稳定性，它们被认为是一种良好的污水处理剂。然而，PAFs的芳香性质使其骨架大多具有疏水性。PAFs的这一特性严重影响其作为吸附剂在水中的扩散速率，导致吸附率较低。在本工作中，我们通过Sonogashira-Hagihara交叉偶联反应合成了一系列羟基官能化的多孔芳香框架（PAF-80、PAF-81和PAF-82），该反应在疏水表面上产生了极性基团，并对水中典型的有机微污染物如双酚A（BPA）、2-萘酚（2-NO）和对氯间二甲苯酚（PCMX）进行了吸附测试。在这三种PAFs中，PAF-82表现出最高的BET比表面积、极性活性位点和高度共轭性，与PAF-80和PAF-81相比，其吸附性能最佳。PAF-82对BPA、2-NO和PCMX的Langmuir吸附容量分别为689 mg g、431 mg g和480 mg g，超过了大多数先前报道的吸附剂。此外，经过5次再生循环后，它对污染物仍保持较高的去除率。所得结果表明，水中微污染物的吸附并非由单一因素控制，而是多种因素协同作用的结果，这些因素包括比表面积、极性官能团、孔径分布和骨架共轭性。我们的研究揭示了羟基PAFs在高效吸附水中有机微污染物方面的巨大潜力。
