摘要:
通过直接聚合反应和重新构建方法分别合成了两种共价有机骨架材料(COFs):DP-COF-1和RC-COF-1,表征了COFs材料的表面形态、结晶度、比表面积、Zeta电位和FTIR光谱等,重点通过吸附动力学模型和吸附等温模型阐明了不同COFs材料对Cr(Ⅵ)的吸附特性差异。结果表明,相比直接合成的DP-COF-1,通过重构方法合成的RC-COF-1具有更稳定的结构以及更高的结晶度和比表面积。伪二级吸附动力学模型和Freundlich吸附等温模型更适合模拟不同COFs材料对Cr(Ⅵ)的吸附过程,COFs材料主要通过化学作用吸附Cr(Ⅵ),且为多层吸附模式。机理分析表明,COFs上含氮和含氧基团主要通过静电吸引和氢键作用吸附水中HCrO4 -/Cr2O7 2-。值得注意的是,RC-COF-1对Cr(Ⅵ)的吸附效果不如DP-COF-1,表明单纯通过提高COFs材料的孔隙度和晶体纯度并不一定能显著提高其吸附性能。
关键词:
共价有机骨架,
吸附,
六价铬,
重构,
直接合成
Abstract:
Two covalent organic frameworks materials(COFs), DP-COF-1 and RC-COF-1, were synthesized by direct polymerization and reconstruction methods, respectively. The surface morphology, crystallinity, specific surface area, Zeta potential, and FTIR spectra of the COFs materials were characterized. The differences in adsorption characteristics of different COFs materials on Cr(Ⅵ) were elucidated by focusing on the adsorption kinetic model and adsorption isotherm model. The results showed that RC-COF-1 synthesized by reconstruction method had more stable structure, higher crystallinity and specific surface area than the directly synthesized DP-COF-1. The pseudo-secondary adsorption kinetic model and Freundlich adsorption isothermal model were more suitable to simulate the adsorption process of Cr(Ⅵ) by different COFs materials. COFs primarily adsorbed Cr(Ⅵ) through chemical interaction, following a multilayer adsorption. The mechanism analysis showed that the nitrogen and oxygen groups on COFs adsorbed HCrO4 -/Cr2O7 2- in water via electrostatic attraction and hydrogen bonding. Notably, the adsorption of Cr(Ⅵ) by RC-COF-1 was not as effective as that of DP-COF-1, indicating that the adsorption performance of the COFs materials was not significantly improved by simply increasing the porosity and crystal purity of the materials.
Key words:
covalent organic frameworks,
adsorption,
Cr(Ⅵ),
reconstruction,
direct synthesis
中图分类号:
杨启帆, 肖国涛, 文一琅, 李德燕, 周双喜, 王维. 重构与直接合成共价有机骨架吸附Cr(Ⅵ)性能对比[J]. 工业水处理, 2025, 45(9): 48-55.
Qifan YANG, Guotao XIAO, Yilang WEN, Deyan LI, Shuangxi ZHOU, Wei WANG. Comparison of Cr(Ⅵ) adsorption performance between reconstituted and directly synthesized covalent organic frameworks[J]. Industrial Water Treatment, 2025, 45(9): 48-55.