CMPO/[C_nmim][NTf_2]体系对Eu^(3+)和UO_2^(2+)的萃取行为  

Extraction Behavior of Eu^(3+) and UO_2^(2+) Using CMPO/[C_nmim][NTf_2] Systems

作　　者：施锦强 袁威津 董珍[1] 赵龙[1] 韦悦周[1] 何林峰[2] 唐方东[2] 

机构地区：[1]上海交通大学核科学与工程学院,上海200240 [2]上海市计量测试技术研究院化学与电离辐射计量技术研究所,上海201203

出　　处：《无机化学学报》2016年第3期414-420,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.11475112);教育部博士点基金项目(No.20130073120051)资助

摘　　要：讨论了辛基(苯基)-N,N-二异丁基胺甲酰基甲基氧化膦(CMPO)/1-烷基-3-甲基咪唑双(三氟甲烷磺酰)亚胺盐([C_nmim][NTf_2],n=2,8,12)萃取体系分别对硝酸溶液中的铕离子(Eu^(3+))和铀酰根离子(UO_2^(2+))的萃取行为。主要研究了硝酸浓度、接触时间、温度、CMPO浓度对CMPO/[C_nmim][NTf_2]体系萃取性能的影响,并选取CMPO/[C_2mim][NTf_2]体系对模拟高放废液中的镧锕元素进行了萃取分离。结果表明:随着离子液体侧链长度增长,萃取平衡时间逐渐延长;CMPO/[C3+2mim][NTf_2]体系对Eu的萃取是放热反应,萃取率随酸度增加而逐渐降低,对UO_2^(2+)则是吸热反应,萃取率随酸度增加而逐渐升高;通过机理研究,推测出对Eu^(3+)的萃取反应是离子交换,而对UO_2^(2+)的萃取反应则是中性配位;CMPO/[C_2mim][NTf_2]体系能有效的萃取模拟高放废液中的镧系、锕系元素,且在高酸下有一定的镧锕分离效果。The extraction behavior of Eu^3＋and UO2^2＋from nitric acid solution with n-Octyl（phenyl）-N,N diisobutylcarbamoylmethylphosphine oxide（CMPO） dissolved in hydrophobic ionic liquid [Cnmim][NTf2]（n=2, 8, 12） was studied. The extraction efficiency（E） of Eu^3＋and UO2^2＋in CMPO/[Cnmim] [NTf2] was measured as a function of various parameters such as contact time, the concentrations of nitric acid, CMPO and temperature. CMPO/[C2mim] [NTf2] system was selected for lanthanide and actinide partitioning from simulated high level waste（SHLW）. The results showed that the extraction equilibrium time extended gradually with the increasing of the chain length of the ionic liquid. The E values for Eu^3＋decreased while that for UO2^2＋increased with the increasing of acidity. The extraction process was endothermic for UO2 ＋2while the same was for Eu3 ＋it was exothermic. The extraction mechanism was suggested that the extraction proceed via ion exchange mechanism for Eu^3＋while that for UO2^2＋via neutral complex. Actinides（An） and lanthanides（Ln） could be extracted effectively from SHLW. And to some extent, An/Ln separation effectiveness was observed under high acidity using CMPO/[C2mim][NTf2] system.

关 键 词：三价铕离子 铀酰根离子 辛基(苯基)-N N-二异丁基氨甲酰基甲基氧化膦 离子液体 萃取 

分 类 号：O614.338[理学—无机化学] O614.62[理学—化学]