(1. 武汉工程大学 绿色化工过程教育部重点实验室 化工与制药学院,武汉430074;
2. 四川文理学院 化学化工学院,达州 635000)
摘 要: 为了从风化壳淋积型稀土矿铵盐浸出液中萃取分离出稀土离子,合成3种3-氧戊二酰胺类萃取剂N,N,N′,N′-四丁基-3-氧戊二酰胺、N,N,N′,N′-四己基-3-氧戊二酰胺和N,N,N′,N′-四辛基-3-氧戊二酰胺。考察在NH4Cl、(NH4)2SO4、NH4NO3这3种铵盐溶液中,萃取剂浓度和不同稀释剂类型对3种3-氧戊二酰胺类萃取剂萃取稀土离子的影响,并筛选出合适的稀释剂。结果表明:在NH4Cl溶液中,以正辛烷-正辛醇(体积比7:3)为稀释剂时,N,N,N′,N′-四丁基-3-氧戊二酰胺的萃取效果最好,对Y离子和Gd离子的单级萃取剂分别为为89%和91%,且萃取率随着萃取剂浓度的增大而增大,在相比为4:6时萃取率达到最大并几乎恒定。在(NH4)2SO4、NH4NO3溶液中,不同稀释剂对萃取效果的影响差别则较小。
关键字: 3-氧戊二酰胺;萃取;铵盐体系;稀土;稀释剂
(1. Key Laboratory for Green Chemical Process of Ministry of Education, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan 430074, China;
2. School of Chemistry and Chemical Engineering, Sichuan University of Arts and Science, Dazhou 635000, China)
Abstract:Three kinds of 3-oxa-glutaramide extractants, N,N,N′,N′-tetrabutyl-3-oxy-glutaramide, N,N,N′,N′-tetrahexyl- 3-oxy-glutaramide, N,N,N′,N′-tetraoctane-3-oxy-glutaramide, were synthesized and characterized. The influences of extractant concentration and different diluents on the extraction behavior of rare earth ions with three kinds of 3-oxa-glutaramide extractants were investigated in three ammonium salt solution of NH4Cl, (NH4)2SO4 and NH4NO3. The results screen out suitable diluents and provide support for optimal extraction process. The extraction efficiency of N,N,N′,N′-tetrabutyl-3-oxy-glutaramide is the best when octane-octanol (volume ratio of 7:3) is used as diluent in NH4Cl system. And the single-stage extractants for Y and Gd are 89% and 91%. And extraction efficiency increases with increasing the extractant concentration. The extraction rates of Y and Gd reach the maximum and almost no change under the phase ratio of 4:6. Different diluents have weak effect on the extraction efficiency in the system of (NH4)2SO4 and NH4NO3.
Key words: 3-oxa-glutaramide; extraction; ammonium salt system; rare earth; diluent