Cocalia Violina A, Jensen Mark P, Holbrey John D, Spear Scott K, Stepinski Dominique C, Rogers Robin D
Department of Chemistry, University of Alabana, Tuscaloosa, AL 35487, USA.
Dalton Trans. 2005 Jun 7(11):1966-71. doi: 10.1039/b502016f. Epub 2005 May 3.
The extraction of both UO2(2+) and trivalent lanthanide and actinide ions (Am3+, Nd3+, Eu3+) by dialkylphosphoric or dialkylphosphinic acids from aqueous solutions into the ionic liquid, 1-decyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide has been studied and compared to extractions into dodecane. Radiotracer partitioning measurements show comparable patterns of distribution ratios for both the ionic liquid/aqueous and dodecane/aqueous systems, and the limiting slopes at low acidity indicate the partitioning of neutral complexes in both solvent systems. The metal ion coordination environment, elucidated from EXAFS and UV-visible spectroscopy measurements, is equivalent in the ionic liquid and dodecane solutions with coordination of the uranyl cation by two hydrogen-bonded extractant dimers, and of the trivalent cations by three extractant dimers. This is the first definitive report of a system where both the biphasic extraction equilibria and metal coordination environment are the same in an ionic liquid and a molecular organic solvent.
研究了用二烷基磷酸或二烷基次膦酸从水溶液中向离子液体1-癸基-3-甲基咪唑双（三氟甲磺酰）亚胺中萃取UO2(2+)以及三价镧系和锕系离子（Am3+、Nd3+、Eu3+）的过程，并与向十二烷中的萃取进行了比较。放射性示踪剂分配测量表明，离子液体/水和十二烷/水体系的分配比模式具有可比性，低酸度下的极限斜率表明中性配合物在两种溶剂体系中的分配情况。通过EXAFS和紫外可见光谱测量阐明的金属离子配位环境在离子液体和十二烷溶液中是相同的，其中铀酰阳离子通过两个氢键连接的萃取剂二聚体配位，三价阳离子通过三个萃取剂二聚体配位。这是关于一个体系的第一份权威性报告，该体系中离子液体和分子有机溶剂中的双相萃取平衡以及金属配位环境均相同。
