Pyridine-based covalent organic framework for efficient and selective removal of Hg(II) from water: Adsorption behavior and adsorption mechanism investigations

被引：69

作者：

Fu, Quanbin ^{[1
,2
]}

Zhang, Tingting ^{[2
,3
]}

Sun, Xin ^{[1
]}

Zhang, Shikai ^{[1
,2
]}

Waterhouse, Geoffrey I. N. ^{[4
]}

Sun, Chuan ^{[5
]}

Li, Houshen ^{[2
,3
]}

Ai, Shiyun ^{[2
,3
]}

机构：

[1] Shandong Agr Univ, Coll Food Sci & Engn, Tai An 271018, Peoples R China

[2] Shandong Agr Univ, Coll Chem & Mat Sci, Tai An 271018, Peoples R China

[3] Minist Agr & Rural Affairs, Key Lab Agr Film Applicat, Tai An 271018, Peoples R China

[4] Univ Auckland, Sch Chem Sci, Auckland 1142, New Zealand

[5] Taian Inst Food & Drug Control, Tai An 271018, Peoples R China

来源：

CHEMICAL ENGINEERING JOURNAL | 2023年 / 454卷

基金：

中国国家自然科学基金;

关键词：

Pyridine-COF; Hg2+adsorption; High adsorption capacity; Density functional theory calculations; VALENCE; HG2+;

D O I：

10.1016/j.cej.2022.140154

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

The high toxicity and carcinogenicity of mercury ions (Hg2+) motivates the development of efficient technologies for their removal from water. In this work, a pyridine-based covalent organic framework (Pyridine-COF) was synthesized via the Schiff base condensation reaction of 1,3,5-tris(4-aminophenyl)benzene (TAP) and 2,6-difor-mylpyridine (DFP) at room temperature. The obtained Pyridine-COF was crystalline, microporous and possessed a high specific surface area (348.5 m2 g-1). The close association of the pyridine linker and imine groups in the COF structure created an N-rich pore space that showed high selectivity towards Hg2+ ions. Adsorption exper-iments showed Pyridine-COF to have very fast Hg2+ adsorption kinetics, a high adsorption capacity for Hg2+ (719.4 mg g-1 at 293 K, 840.3 mg g-1 at 303 K, and 1000 mg g-1 at 313 K), and very good Hg2+ removal performance in the presence of other metal cations. Further, Pyridine-COF maintained a high adsorption capacity over five cycles of adsorption-desorption, confirming good reusability as an adsorbent. Mechanistic studies using X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that the adsorption of Hg2+ in the pores of Pyridine-COF was mainly chelation not covalent interactions. Pyridine-COF represents one of the best COF-based adsorbents developed to date for the removal of Hg2+ from water.

引用

页数：9