N,N'-二甲基-N,N'-二辛基-3-氧戊二酰胺从盐酸介质中萃取三价镧系金属的研究

摘要

以煤油/辛醇(7:3,V/V)为稀释剂,研究N,N',二甲基-N,N'-二辛基-3-氧戊二酰胺(DMDODGA)从盐酸介质中萃取三价镧系金属的性能及反应机理;考察了水相盐酸浓度、萃取剂浓度及温度对其萃取性能的影响.结果表明分配比在所研究酸度范围内随盐酸浓度的增加先增大后减小;随萃取剂浓度的增加而增大;萃合物的组成为MCI3·2DMDODCA(M=Sm,Gd,Dy)或MCI3·DMDODGA(M=Er,Lu).萃取过程为放热反应,升高温度不利于萃取.同时计算出了萃取反应的平衡常数及热力学函数.萃合物的红外光谱表明羰基氧、醚氧均与镧系离子配位.%The extraction performance and mechanism of Lanthanides(Ⅲ) with N,N'-dimethyl-N,N'-dioctyl-3-oxyglutaramide (DMDODGA) in kerosene-octanol (7:3,V/V) from hydrochloric acid medium were studied. The influence of the concentration of hydrochloric acid, DMDODGA and the temperature on the extraction had been investigated. The results show that the extraction distribution ratio of Lanthanides(Ⅲ) firstly increases and then decreases with the increase in the concentration of hydrochloric acid. Extraction distribution increases with the increase in extractant concentration. The stoichiometries of the extracted species are MCl3·2DMDODGA (M=Sm,Gd, Dy) or MCl3·DMDODGA (M=Er, Lu). The distribution ratio decreases with the increase in the temperature,and the extraction reaction is exothermic. The IR spectra of the extracted species indicates that the carbonyl oxygen and etheric oxygen of DMDODGA are all coordinated with lanthanide ions.