磷酸三异戊酯、磷酸三仲丁酯对U(Ⅵ)、Th(Ⅳ)的萃取性能

Extraction Behavior of U(Ⅵ) and Th(Ⅳ) by Tri-Iso-Amyl Phosphate and Tri-Sec-Butyl Phosphate

摘要: 研究了磷酸三异戊酯(TiAP)、磷酸三仲丁酯（TsBP）的正十二烷溶液从硝酸介质中萃取U(Ⅵ)、Th(Ⅳ)的性能及Th(Ⅳ)的萃取容量，并在相同条件下与磷酸三丁酯(TBP)的萃取性质进行了比较。结果表明：TiAP对Th(Ⅳ)、U(Ⅵ)的萃取性能与TBP相近，相同酸度情况下，分配比均略高于TBP；TsBP萃取U(Ⅵ)的分配比高于TBP，而萃取Th(Ⅳ)的分配比低于TBP。随着水相硝酸浓度的增大，两种萃取剂对Th(Ⅳ)、U(Ⅵ)的萃取分配比增大，但在较高酸度下则相反；同时比较了TiAP、TsBP、TBP对Th(Ⅳ)的萃取容量。

Abstract: This paper reports the data on the extraction of U(Ⅵ) and Th(Ⅳ) from different concentration of nitric acid, and the extraction capacity of thorium by tri-iso-amyl phosphate (TiAP), tri-sec-butyl phosphate(TsBP) in n-dodecane solution, at the same time, provides a comparison of their extraction behavior with that of tri-n-butyl phosphate(TBP). The results indicate that extraction properties of U(Ⅵ) and Th(Ⅳ) by TiAP are similar to TBP, and the distribution ratios are slightly higher than that of TBP; while the distribution ratio of U(Ⅵ) by TsBP is higher than that of TBP, but the distribution ratio for Th(Ⅳ) is lower. The distribution ratios of thorium and uranium by the two kinds of extractants are increasing with the increase of nitric acid concention in aqueous phase, then decreasing under the higher acid concention.