磷酸三丁酯(TBP)和丁基膦酸二丁酯(DBBP)协同萃取硝酸铀酰的研究

STUDY ON THE SYNERGISTIC EXTRACTION OF URANYL NITRATE BY TRIBUTYL PHOSPHATE (TBP)-DIBUTYL BUTYL PHOSPHONATE (DBBP) MIXTURE

摘要: 本文研究了磷酸三丁酯和丁基膦酸二丁酯煤油溶液对硝酸铀酰的协同萃取。发现在萃取剂克分子比TBP:DBBP=5:1时出现明显的协同效应;经测定,协萃络合物的组成为UO_2(NO_3)_2·TBP·DBBP,并求得其生成常数K_(TD)=258±32。初步讨论了协萃机理和协萃络合物的可能结构。研究了萃取剂总浓度和克分子比、硝酸浓度、温度和硫酸根浓度等因素对萃取过程的影响。对协萃分配比的实验值和计算值进行了比较,结果基本一致。

Abstract: In this paper the synergistic extraction by a mixture of tributyl phosphate (TBP) and dibutyl butyl phosphonate (DBBP) for uranyl nitrate is studied. It has been found that maximum synergistic extraction effect occurs where the molar ratio of tributyl phosphate to dibutyl butyl phosphonate is five to one. The composition of the complex of synergistic extraction is UO2 (NO3)2·TBP·DBBP.The formation constant of the complex KTD=258±32. Mechanism of synergistic extraction and a possible structure of the complex is proposed.The effect of the total extractant concentration, concentration of nitric acid, temperature and concentration of sulphate on the distribution ratio of uranium is studied. The measured values of the distribution ratio of synergistic extraction agree quite well with the calculated values.