Robust metal–organic framework with multiple traps for trace Xe/Kr separation  

具有多个陷阱的稳定金属-有机网格用来分离痕量氙/氪

作　　者：Huiping Zhang Yaling Fan Rajamani Krishna Xuefeng Feng Li Wang Feng Luo 张辉平;范亚玲;Rajamani Krishna;冯雪风;王丽;罗峰(School of Biology,Chemistry and Material Science,East China University of Technology,Nanchang 344000,China;Van’t Hoff Institute for Molecular Sciences,University of Amsterdam,1098 XH Amsterdam,the Netherlands)

机构地区：[1]School of Biology,Chemistry and Material Science,East China University of Technology,Nanchang 344000,China [2]Van’t Hoff Institute for Molecular Sciences,University of Amsterdam,1098 XH Amsterdam,the Netherlands

出　　处：《Science Bulletin》2021年第11期1073-1079,M0003,共8页科学通报（英文版）

基　　金：supported by the National Natural Science Foundations of China(21966002 and 21871047);the Natural Science Foundation of Jiangxi Province(20181ACB20003);the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(20194BCJ22010);the Graduate Innovation Project of East China University of Technology(DHYC-202023)。

摘　　要：Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(MOF),namely ECUT-60,which renders not only high chemical stability,but also unique structure with multiple traps.This leads to the ultrahigh Xe adsorption capacity,exceeding most reported porous materials.Impressively,this MOF also enables high selectivity of Xe over Kr,CO2,O2,and N2,leading to the high-performance separation for trace quantitites of Xe/Kr from a simulated UNF reprocessing off-gas.The separation capability has been demonstrated by using dynamic breakthrough experiments,giving the record Xe uptake up to 70.4 mmol/kg and the production of 19.7 mmol/kg pure Xe.Consequently,ECUT-60 has promising potential in direct production of Xe from UNF off-gas or air.The separation mechanism,as unveiled by theoretical calculation,is attributed to the multiple traps in ECUT-60 that affords rigid restrict for Xe atom via van der Waals force.对于氙/氪,最理想的做法是用多孔吸附剂直接从空气或核燃料循环尾气中分离氙/氪,但是这是一项具有挑战性的任务.本研究合成了一个具有高化学稳定性的金属-有机框架多孔材料,它具有独一无二的多陷阱孔特征.该特征不仅赋予该多孔材料超高且优于其他吸附材料的氙饱和吸附容量,针对其他气体(如氪、二氧化碳、氧气、氮气)的吸附选择性,同时表现出了优异的动态分离能力,在模拟的核燃料循环尾气中该材料能获得世界纪录的70.4 mmol/kg氙储存能力以及19.7 mmol/kg的纯氙生产能力.这些结果表明,该材料可望用于直接从空气或核燃料循环尾气中分离氙/氪.理论计算表明该材料分离氙/氪的机理主要是其独一无二的多陷阱孔特征,它通过范德华力牢固地捆绑氙原子,从而实现高效、高选择性吸附氙.

关 键 词：Xe/Kr separation MOFs UNF off-gas Multiple traps 

分 类 号：TQ424[化学工程] X701[环境科学与工程—环境工程]