冠醚-离子液体体系对水相中锶离子的萃取研究  

Investigation on the extraction of strontium ions from aqueous phase using crown ether-ionic liquid systems

作　　者：徐超[1] 沈兴海[1] 陈庆德[1] 高宏成[1] 

机构地区：[1]北京分子科学国家实验室、北京大学化学与分子工程学院应用化学系,北京100871

出　　处：《中国科学（B辑）》2009年第11期1402-1408,共7页Science in China(Series B)

基　　金：国家自然科学基金(批准号:20871009)资助

摘　　要：本文研究了以一系列离子液体作为介质时,萃取剂二环己基18冠6(DCH18C6)对水相中Sr2+的萃取行为.研究结果表明,DCH18C6/离子液体体系对Sr2+的萃取性能优于相应的DCH18C6/正辛醇萃取体系,一定条件下其萃取Sr2+的分配比可达103量级.同时,体系对Sr2+的萃取性能随着离子液体的结构不同而有所差别.在离子液体萃取体系中,随着水相初始硝酸浓度的增加,对Sr2+的萃取性能下降.水相中Na+、K+等离子的存在也会对体系萃取Sr2+产生直接影响.本文还验证了离子液体体系萃取Sr2+的机理,即以阳离子交换机理为主实现对Sr2+的萃取.The extraction of Strontium using DCH18C6 as extractant and various ionic liquids （ILs） as solvents has been investigated. The distribution ratio of SrSr^2＋ can reach as high as 10^3 under certain conditions, much larger than that in DCH18C6/n-Octanol system. The extraction capacity depends greatly on the structure of ionic liquids. In ILs based extraction systems, the extraction efficiency of Strontium ions is reduced by increasing the concentration of nitric acid and can also be influenced directly by the presence of Na^＋, K^＋ in the aqueous phase. It is confirmed that the extraction proceeds mainly via a cation-exchange mechanism.

关 键 词：锶离子 离子液体 萃取 冠醚 

分 类 号：O652.62[理学—分析化学]