School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, No.9 Yinbing Avenue, Yancheng, 224002, China.
Comprehensive Testing Center, Yancheng Customs, No.85 Kaifang Avenue, Yancheng, 224002, China.
Anal Sci. 2022 Feb;38(2):383-392. doi: 10.2116/analsci.21P279. Epub 2022 Mar 22.
The functionalization of porous aromatic frameworks (PAFs) is essential for task-specific application of these materials as advanced adsorbents in water treatment. In this study, a carboxyl-functionalized PAF was prepared by the post-synthesis modification of a HOCH-tagged PAF, which was synthesized from a precursor-designed method. The synthesized PAFs were comprehensively characterized. The targeted PAF-COOH showed hierarchical porosity with the coexistence of micropores and mesopores. The carboxyl groups were distributed homogeneously across the whole material, and its content was as high as 4.18 meq g. An equilibrium adsorption isotherms study demonstrated that the adsorption of cationic dyes fitted well to the Langmuir model and the maximum adsorption capacities of methylene blue (b-MB) and phenosafranine obtained at pH 10 were 775.19 and 588.24 mg g, respectively. The adsorption kinetics of cationic dyes followed the pseudo-second order kinetic model. Quick kinetics was demonstrated with the k for a 100 mg L b-MB solution as high as 2.83 g mg min and the equilibrium time was just 0.5 min. In addition, the dye-loaded PAF-COOH could be regenerated easily and showed excellent reusability. These significant characters indicated a promising prospect of the PAF-COOH for water treatment.
多孔芳香骨架（PAFs）的功能化对于这些材料作为水处理中先进吸附剂的特定应用至关重要。在本研究中，通过对 HOCH 标记的 PAF 进行后合成修饰，制备了一种羧基功能化的 PAF，该 PAF 是通过前体制备方法合成的。对合成的 PAF 进行了全面的表征。目标 PAF-COOH 具有微孔和介孔共存的分级多孔性。羧基均匀分布在整个材料中，其含量高达 4.18 meq g。平衡吸附等温线研究表明，阳离子染料的吸附很好地符合朗缪尔模型，在 pH 值为 10 时，亚甲蓝（b-MB）和酚红的最大吸附容量分别为 775.19 和 588.24 mg g。阳离子染料的吸附动力学符合准二级动力学模型。对于 100 mg L b-MB 溶液，k 值高达 2.83 g mg min，平衡时间仅为 0.5 min，表现出快速动力学。此外，负载染料的 PAF-COOH 易于再生，具有优异的可重复使用性。这些显著的特性表明 PAF-COOH 在水处理方面具有广阔的前景。
