ABSTRACT

Studies have been performed with the purpose of determining the optimal solvent composition of a Chalmers grouped actinide extraction (CHALMEX) solvent for the selective co-extraction of transuranic elements in a novel Grouped ActiNide EXtraction (GANEX) process. The solvent is composed of 6,6’-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo-[1,2,4]-triazin-3-yl)-[2,2’]-bipyridine (CyMe₄-BTBP) and tri-n-butyl phosphate (TBP) in phenyl trifluoromethyl sulfone (FS-13). The performance of the system has been shown to significantly depend on the ratios of the two extracting agents and the diluent to one another. Furthermore, the performance of the determined optimal solvent (10 mM CyMe₄-BTBP in 30% v/v TBP and 70% v/v FS-13) on various simulated PUREX raffinate solutions was tested. It was found that the solvent extracts all transuranic elements with high efficiency and good selectivity with regard to most other elements (fission products/activation products) present in the simulated PUREX raffinate solutions. Moreover, the solvent was found to extract a significant amount of acid. Palladium, silver, and cadmium were co-extracted along with the TRU-radionuclides, which has also been observed in other similar CHALMEX systems. The extraction of plutonium and uranium was preserved for all tested simulated PUREX raffinate solutions compared to experiments using trace amounts.

摘要

为了确定一种新颖的成组的ActiNide萃取（GANEX）工艺中的超铀元素的选择性共萃取，已经确定了Chalmers组的act系元素萃取（CHALMEX）溶剂的最佳溶剂组成。溶剂由6,6'-双（5,5,8,8-四甲基-5,6,7,8-四氢-苯并-[1,2,4]-三嗪-3-基）-[ 2,2' ] -联吡啶（CYME ₄ -BTBP）和三- ñ丁基磷酸酯（TBP）中的苯基三氟甲基砜（FS-13）。已显示该系统的性能在很大程度上取决于两种萃取剂和稀释剂之间的比例。此外，确定的最佳溶剂（10 mM CyMe ₄在各种模拟的PUREX提余液中测试了30％v / v TBP和70％v / v FS-13中的-BTBP。已发现，相对于模拟的PUREX提余液中存在的大多数其他元素（裂变产物/活化产物），溶剂能高效，高选择性地萃取所有超铀元素。此外，发现溶剂萃取出大量的酸。钯，银和镉与TRU-放射性核素一起被共萃取，这在其他类似的CHALMEX系统中也可以观察到。与使用痕量实验相比，所有测试过的模拟PUREX提余液均保留了and和铀的萃取物。