title: A novel benzimidazole-functionalized 2-D COF material: synthesis and application as a selective solid-phase extractant for separation of uranium.
abstract: A novel COF-based material (COF-COOH) containing large amounts of carboxylic groups was prepared for the first time by using a simple and effective one-step synthetic method, in which the cheap and commercially available raw materials, trimesoyl chloride and p-phenylenediamine, were used. The as-synthesized COF-COOH was modified with previously synthesized 2-(2,4-dihydroxyphenyl)-benzimidazole (HBI) by "grafting to" method, and a new solid-phase extractant (COF-HBI) with highly efficient sorption performance for uranium(VI) was consequently obtained. A series of characterizations demonstrated that COF-COOH and COF-HBI exhibited great thermostabilities and irradiation stabilities. Sorption behavior of the COF-based materials toward U(VI) was compared in simulated nuclear industrial effluent containing UO2(2+) and 11 undesired ions, and the UO2(2+) sorption amount of COF-HBI was 81 mg g(-1), accounting for approximately 58% of the total sorption amount, which was much higher than the sorption selectivity of COF-COOH to UO2(2+) (39%). Batch sorption experiment results indicated that the uranium(VI) sorption on COF-HBI was a pH dependent, rapid (sorption equilibrium was reached in 30 min), endothermic and spontaneous process. In the most favorable conditions, the equilibrium sorption capacity of the adsorbent for uranium could reach 211 mg g(-1).
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Yang
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Chiyao
authors.initials: C
authors.lastname: Bai
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Tian
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Yang
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Songdong
authors.initials: S
authors.lastname: Ding
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Chuanqin
authors.initials: C
authors.lastname: Xia
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Tan
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China. Electronic address: ma.lj@163.com.
authors.forename: Lijian
authors.initials: L
authors.lastname: Ma
authors.affiliation: College of Chemistry, Sichuan University, Key Laboratory of Radiation Physics & Technology (Sichuan University), Ministry of Education, Chengdu 610064, PR China. Electronic address: sjli000616@scu.edu.cn.
authors.forename: Shoujian
authors.initials: S
authors.lastname: Li
mesh_terms: D001562:Benzimidazoles / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D066244:Proton Magnetic Resonance Spectroscopy; D052616:Solid Phase Extraction / Q000295:instrumentation*; D017550:Spectroscopy, Fourier Transform Infrared; D014501:Uranium / Q000302:isolation & purification*
chemical_list: D001562:Benzimidazoles; D014501:Uranium
keywords: Covalent organic frameworks (COFs); Modified; Selective sorption; Solid-phase extractant; Uranium