原子能科学技术2026，Vol.60Issue(3)：523-531,9.DOI:10.7538/yzk.2025.youxian.0427
水溶液中N-三(2-氨基乙基)胺-N',N',N'',N'',N''',N'''-六乙酸与U(Ⅵ)的配位化学研究
Coordination Chemistry of U(Ⅵ)and N-tris(2-aminoethyl)amino-N',N',N'',N'',N''',N'''-hexaacetic Acid in Aqueous Solution
摘要
Abstract
Uranium,as one of the actinide metal elements with relatively high abundance in nature,its natural existence forms are of great significance for research on environmental and chemical behaviors.Typically,it exists in the+6 oxidation state as UO22+,especially in aqueous solutions under aerobic conditions.N-tris(2-aminoethyl)amine-N',N',N'',N'',N''',N'''-hexaacetic acid(TTAHA,H6L),as a typical amino polycarboxylic acid ligand,exhibits rich coordination ability and diversity due to its multiple coordinating groups.It can form stable coordination complexes with different metal ions through various binding modes,depending on their charge,radius,and other characteristics.However,based on a review of current literature,although the TTAHA ligand has been widely studied with various metal ions,detailed chemical research on its coordination mechanism with uranium has not been systematically reported,and this field remains in the exploratory stage.In this paper,potentiometry was used to determine the seven protonation constants of TTAHA at INaClO4=1.0 mol/L.Subsequently,a combination of potentiometry and spectrophotometry identified five U(Ⅵ)-TTAHA complexes,namely(UO2)2LH2,(UO2)2LH-,UO2LH3-,UO2L4-,and UO2L(OH)5-.The stability constants and molar absorption spectra of these complexes were calculated.The structures of the U(Ⅵ)-TTAHA complexes were inferred using Raman spectroscopy.The(UO2)2LH-complex adopts O-N-O tridentate coordination,involving two oxygen atoms from two carboxylic groups and one nitrogen atom from the amine group.Furthermore,the UO2LH3-complex exhibits O-N-N-O tetradentate coordination.In summary,the systematic data obtained in this study,including protonation constants,the precise chemical composition of each uranyl complex and their corresponding stability constants,as well as the molar absorption spectra of key representative complex species.The obtained data provide basic parameters for the study of the coordination interaction between TTAHA and uranium ions.The determination of the complex composition,stability constants,and coordination patterns provides experimental and theoretical basis for understanding the interaction mechanism between amino polycarboxylic acid ligands and uranium.关键词
氨基多羧酸/铀酰/TTAHA/稳定常数/配位模式Key words
aminopolycarboxylic acid/uranyl/TTAHA/stability constant/coordination mode分类
能源科技引用本文复制引用
吕弈霏,张倩慈,杨素亮,张燕,柳倩,王琛,田国新..水溶液中N-三(2-氨基乙基)胺-N',N',N'',N'',N''',N'''-六乙酸与U(Ⅵ)的配位化学研究[J].原子能科学技术,2026,60(3):523-531,9.基金项目
核能开发科研项目(HNKF202232(36)) （HNKF202232(36）
