酰胺荚醚类萃取剂结构对Gd(Ⅲ)萃取性能的影响

Effect of 3-Oxy-diglycolamides Structure on the Extraction Behavior of Gd(Ⅲ)

本文合成了4种新型不对称酰胺荚醚萃取剂:N,N′-二甲基-N,N′-二苯基-3-氧戊二酰胺(DMDPhDGA)、N,N′-二甲基-N,N′-二己基-3-氧戊二酰胺(DMDHDGA)、N,N′-二甲基-N,N′-二辛基-3-氧戊二酰胺(DMDODGA)、N,N′-二甲基-N,N′-二癸基-3-氧戊二酰胺(DMDDDGA)。以氯仿为稀释剂,研究了N,N,N′,N′-四丁基-3-氧戊二酰胺(TBDGA)及上述4种萃取剂从硝酸体系中萃取Gd(Ⅲ)的反应机理,得出萃取能力顺序为:DMDHDGA>DMDDDGA>DMDODGA>DMDPhDGA>TBDGA。考察了水相酸度和萃取剂浓度对萃取分配比的影响,得出萃合物中有3个萃取剂分子同时参与配位;并结合红外光谱解释了萃取剂结构与萃取性能的关系。

Four asymmetric diglycolamides： N,N＇-dimethyl-N,N＇-diphenyl-3-oxa-diglycolamide （DMDPhDGA）, N, N＇-dimethyl-N,N＇-dideeyl-3-oxa-diglycolamide （DMDDDGA）, N,N＇-dimethyl-N,N＇-dihexyl-3-oxa-diglycolamide （DMDHDGA）, N,N＇-dimethyl-N,N＇-dioetyl-3-oxa-diglyeolamide （DMDODGA） were synthesized. The extraction of Gd（Ⅲ） with N,N,N＇,N＇-tetrabutyl-3-oxa-diglycolamide （TBDGA） and the above extractants from nitric acid using CHCl3 as diluent was studied. The extraction capability decrease in the order： DMDHDGA 〉DMDDDGA 〉 DMDODGA 〉DMDPhDGA 〉TBDGA. The effect of water phase acidity and concentration of extraetant on the extraction distribution ratio has been measured. The extraction mechanism has been shown that three extractant molecules were coordinated to a metal ion. The structure-function relationship was explained by IR spectra.