TODGA-TBP-OK体系对Sr(Ⅱ)、Eu(Ⅲ)萃取性能的研究

Extraction Behavior of Sr(Ⅱ)and Eu(Ⅲ)in TODGA-TBP-OK System

通过实验研究了以TODGA为萃取剂、TBP为改良剂、煤油为稀释剂的萃取体系在酸性溶液中对Sr(Ⅱ)、Eu(Ⅲ)的萃取性能的影响因素。结果表明:料液中HNO_(3)浓度在0.1~3.4 mol/L范围内,Sr(Ⅱ)分配系数随酸度的升高而增大;0.05mol/L的TODGA对Eu(Ⅲ)的萃取能力远远大于Sr(Ⅱ),可以实现料液中Sr(Ⅱ)与Eu(Ⅲ)的有效分离;Sr(Ⅱ)的分配系数随着料液浓度的升高而略有降低;TODGA萃取Sr(Ⅱ)的反应为放热反应,Sr(Ⅱ)的分配系数随温度的升高而降低;TODGA对Eu(Ⅲ)的萃取能力较强,料液酸度、浓度及环境温度变化对Eu(Ⅲ)分配系数影响不明显。

The influence factors of extraction performance of Sr(Ⅱ)and Eu(Ⅲ)in acidic solution with TODGA as extractant,TBP as modifier and kerosene as diluent were studied experimentally.The results show that the Sr(Ⅱ)distribution coefficient increases with the increase of acidity in the range of 0.1-3.4 mol/L HNO_(3) concentration.The extraction capacity of Eu(Ⅲ)with 0.05 mol/L TODGA is much larger than that of Sr(Ⅱ),which can effectively separate Sr(Ⅱ)from Eu(Ⅲ)in the feed liquid.The distribution coefficient of Sr(Ⅱ)decreases slightly with the increase of feed liquid concentration.The extraction of Sr(Ⅱ)by TODGA is exothermic,and the distribution coefficient of Sr(Ⅱ)decreases with the increase of temperature.TODGA has strong extraction ability for Eu(Ⅲ),and the acidity,concentration and ambient temperature of feed liquid have no obvious effect on the Eu(Ⅲ)partitioning coefficient.