Three pyridine-based aqueous complexants have been synthesized and evaluated for their utility in an unbuffered TALSPEAK (Trivalent Actinide Lanthanide Separation by Phosphorus-reagent Extraction from Aqueous Komplexes) separation system as trivalent actinide-selective holdback reagents. The selectivity was established based on distribution studies using radiotracer ^152/154Eu, ²⁴¹Am, stable Ln, Y, and Th. In this system, these ligands selectively sequester Am from the lanthanides without the need for a secondary pH buffer. Am-lanthanide single-stage separation factors for Eu were found to be >70 for all three ligands and >15 for Nd. The results demonstrate that aqueous pyridine-based ligands represent viable alternatives to conventional aminopolycarboxylate complexants as actinide-selective holdback reagents in TALSPEAK-based actinide-lanthanide separation systems.

合成了三种基于吡啶的水性络合剂，并评估了它们在无缓冲的TALSPEAK（通过从水性Komplexes中提取磷试剂从磷中分离出三价Act系元素镧系元素）分离系统作为三价act系选择性保留剂的效用。选择性是根据使用放射性示踪剂^152/154 Eu，^241的分布研究确定的是，稳定的Ln，Y和Th。在该系统中，这些配体选择性地从镧系元素螯合Am，而无需辅助pH缓冲剂。发现所有三个配体的Eu的镧系元素单阶段分离因子> 70，而Nd> 15。结果表明，在基于TALSPEAK的act系元素-镧系元素分离系统中，基于吡啶基的水性配体可作为常规氨基聚羧酸盐络合物的替代品，作为act系元素选择性保留试剂。