ABSTRACT

A new N-atom donor extractant 2,9-bis(1-(2-ethylhexyl)-1H-1,2,3-triazol-4-yl)-1,10-phenanthroline (EH-BTzPhen) was synthesized and used in solvent extraction studies to separate the trivalent minor actinide americium(III) and curium(III) from europium(III), representing fission product lanthanides. The extractant was found to be soluble in 1-octanol and in the Aliquat-336 nitrate ([A336][NO₃]) ionic liquid diluent, but insoluble in n-dodecane. The [A336][NO₃] is a fully incinerable room temperature ionic liquid, and has a higher flash point than aliphatic diluents such as 1-octanol. The EH-BTzPhen proved to be effective for selective minor actinide extraction only in combination with 2-bromohexanoic acid synergist when 1-octanol was used as a diluent (SF _Am/Eu > 200). The change of the diluent from 1-octanol to Aliquat-336 nitrate allowed selective An(III) extraction from low acidity feed solutions without the need of a synergist (SF _Am/Eu ~ 70 and SF _Am/Cm ~ 1.9–2.2). The phase transfer kinetics of the ligand-metal complexes is however very slow at 22 °C in the case of both solvents. With this newly synthesized extractant, the achieved SF _Am/Cm was comparable to the values achieved with the established CyMe₄BTBP and CyMe₄BTPhen extractants.

摘要

合成了一种新的N原子供体萃取剂2,9-双（1-（2-乙基己基）-1 H -1,2,3-三唑-4-基）-1,10-菲咯啉（EH-BTzPhen）并用于溶剂萃取研究中，从euro（III）中分离出三价次要act系元素a（III）和cur（III），代表裂变产物镧系元素。发现萃取剂可溶于1-辛醇和硝酸盐的Aquaqua-336（[A336] [NO ₃ ]）离子液体稀释剂，但不溶于正十二烷。[A336] [NO ₃]是完全可焚化的室温离子液体，并且具有比脂族稀释剂（例如1-辛醇）更高的闪点。当将1-辛醇用作稀释剂（SF _{Am / Eu} > 200）时，EH-BTzPhen仅与2-溴己酸协同剂结合使用，对选择性次act系元素的萃取有效。将稀释剂从1-辛醇更改为Aliquat-336硝酸盐，可从低酸度进料溶液中选择性提取An（III），而无需增效剂（SF _{Am /} Eu〜70和SF _{Am /} Cm〜1.9–2.2）。然而，在两种溶剂中，配体-金属配合物的相转移动力学在22°C时都非常慢。使用这种新合成的萃取剂，可获得的SF _{Am / Cm}与建立的CyMe ₄ BTBP和CyMe ₄ BTPhen萃取剂所获得的值相当。