Stable Covalent Organic Frameworks as Efficient Adsorbents for High and Selective Removal of an Aryl-Organophosphorus Flame Retardant from Water
Stable Covalent Organic Frameworks as Efficient Adsorbents for High and Selective Removal of an Aryl-Organophosphorus Flame Retardant from Water
复制标题
稳定的共价有机框架作为高效吸附剂，用于高效、选择性地去除水中的芳基有机磷阻燃剂
DOI：
10.1021/acsami.8b06229
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发表时间：
2018
影响因子：
9.5
通讯作者：
Yu Gang
中科院分区：
文献类型：
--
作者：
Wang Wei;Deng Shubo;Ren Lu;Li Danyang;Wang Wenjing;Vakili Mohammadtaghi;Wang Bin;Huang Jun;Wang Yujue;Yu Gang
环境修复的一个关键挑战是设计具有适当孔径的吸附剂来去除有机污染物。通过室温溶液悬浮法成功制备了三种不同孔径的共价有机骨架（COF），并用于从水溶液中去除典型的芳基有机磷阻燃剂[磷酸三苯酯（TPhP）]。制备的COFs表现出很强的耐酸性和热稳定性。 1,3,5-三甲酰间苯三酚（TFP）与联苯胺（BD）（COF2）反应，对TPhP表现出最高的吸附容量，其次是TFP与4,4''-二氨基对三联苯（DT）（COF3）的反应，以及TFP与对苯二胺（COF1）的反应。它们在12小时内达到吸附平衡，孔径较大的COF具有较高的初始吸附率，但达到吸附平衡的时间较长。根据Langmuir拟合，三种COF对TPhP的最大吸附容量分别为86.1、387.2和371.2 mg/g。密度泛函理论计算证明，孔径较小的COF1会阻碍TPhP分子进入孔隙，导致吸附容量极低，而孔径相对较大的COF3会降低吸附能，也不利于TPhP的吸附。此外，所制备的COF可以在共存化合物存在的情况下选择性吸附TPhP，并且对实际城市废水中的TPhP具有较高的去除率，显示出通过精确控制COF结构选择性去除水中微污染物的良好应用潜力。
A critical challenge in environmental remediation is the design of adsorbents with proper pore size for the removal of organic pollutants. Three covalent organic frameworks (COFs) with different pore sizes were successfully prepared by a room-temperature solution-suspension method and used to remove a typical aryl-organophosphorus flame retardant [triphenyl phosphate (TPhP)] from aqueous solution. The prepared COFs showed strong acid resistance and thermal stability. The 1,3,5-triformylphloroglucinol (TFP) reacted with benzidine (BD) (COF2) and exhibited the highest sorption capacity for TPhP, followed by the reaction of TFP and 4,4 ''-diamino-p-terphenyl (DT) (COF3), and the reaction of TFP and p-phenylenediamine (COF1). Their adsorption equilibriums were achieved within 12 h, and COFs with a larger pore size have higher initial sorption rate but longer time to reach sorption equilibrium. According to the Langmuir fitting, the maximum sorption capacities of three COFs for TPhP were 86.1, 387.2, and 371.2 mg/g, respectively. The density functional theory calculation verified that COF1 with a small pore size prevents TPhP molecules from entering the pores, resulting in extremely low sorption capacity, whereas a relatively too large pore size (COF3) will decrease the sorption energy, which is also not conducive to the adsorption of TPhP. Moreover, the prepared COFs can selectively adsorb TPhP in the presence of coexisting compounds and had high removal of TPhP from actual municipal wastewater, showing a promising application potential for selective removal of micropollutants from water by precisely controlling the COF structure.