摘要
在乏燃料后处理及核环境修复等领域,设计合成高效、高选择性分离TcO-4及其模拟物ReO-4的吸附剂材料具有重要意义。共价有机框架(COF)材料是一种结晶多孔聚合物材料,在放射性核素分离方面具有独特优势。本研究首先合成一种富含乙烯基的二维COF材料(TbDa-COF),通过γ射线预辐射引发接枝方法,将离子液体1-乙烯基-3-乙基咪唑溴盐(C_(2)vimBr)成功接枝到TbDa-COF上,辐射接枝后材料仍保持良好的结晶性和多孔性。结果表明,影响接枝率的主要因素为单体溶液浓度,随着C_(2)vimBr浓度增加,接枝率呈上升趋势,而溶剂种类对接枝率的影响较小。所制备的[C_(2)vimBr]-TbDa-COF材料对ReO-4具有优异的吸附分离性能,可在2 min内达到吸附平衡,饱和吸附量可达420 mg/g,而在接枝链上引入长链疏水基团有助于提升吸附选择性。本研究展现了离子液体修饰COF材料在乏燃料后处理及核环境修复中的巨大潜力。
In the fields of spent fuel reprocessing and nuclear environmental remediation,it is important to design and synthesize adsorbent materials with high efficiency and selectivity for separating TcO-4 and its analog ReO-4.The porous and crystalline covalent organic framework(COF)materials show unique advantages in radionuclide separation.In this work,a vinyl-rich two-dimensional COF material(TbDa-COF)was synthesized firstly.The ionic liquid 1-vinyl-3-ethyl imidazolium bromide(C_(2)vimBr)as a monomer was successfully grafted onto TbDa-COF by usingγ-ray pre-irradiation induced grafting polymerization.The crystallinity and porosity of the TbDa-COF remains after grafting with ionic liquid.The effect of concentration of ionic liquid monomer on the grafting is the most important.The grafting yield increases with the rising of monomer content,and solvent has slight effect on the grafting yield of products.The prepared[C_(2)vimBr]-TbDa-COF material shows excellent adsorption performance for ReO-4.The adsorption equilibrium can be reached within 2 min,and the maximum adsorption capacity is up to 420 mg/g.The introduction of long hydrophobic alkyl groups on the graft chain in[C_(2)vimBr]-TbDa-COF is conducive to improving the adsorption selectivity towards ReO-4.This work demonstrates the great potential of ionic liquid modified COF for spent fuel reprocessing and nuclear environmental remediation.
作者
张书铭
王月
李久强
彭静
翟茂林
ZHANG Shuming;WANG Yue;LI Jiuqiang;PENG Jing;ZHAI Maolin(College of Chemistry and Molecular Engineering,Peking University,Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science,Beijing National Laboratory for Molecular Science,Beijing 100871,China)
出处
《同位素》
CAS
2023年第5期499-507,共9页
Journal of Isotopes
基金
国家自然科学青年基金(12205009)
中国博士后科学基金(2022M710197,2023T160018)。
关键词
共价有机框架
离子液体
辐射接枝
吸附分离
高铼酸根
covalent organic framework(COF)
ionic liquid
radiation grafting
adsorption separation
perrhenate
