(TTA+N503)协萃U(Ⅵ)的机理研究

SYNERGISTIC EXTRACTION OF URANYL NITRATE BY BINARY SYSTEM OF AB SPECIES COMPOSED OF TTA-N503 IN BENZENE

摘要: <正> 一、前言自1956年Blake等发现协萃现象后,国内外科学家做了大量的研究,并总结了协同萃取规律。到80年代初王文清等发现了三元协萃现象,并研究了其反应机理。与此同时,协同萃取已被应用于科研和生产,特别是锕系和镧系的提取及分离。我们用噻吩甲酰三氟丙酮(TTA)从硝酸底液里萃取U(Ⅵ)的实验中发现TTA和N,N-(1-甲庚基)乙酰胺(N_(503))的协萃效应相当明显,协萃系数高达672,且N_(503)是一种便宜的试剂。本文探讨其协萃机理。

Abstract: The synergistic extraction of uranyl nitrate with binary system of thenoyl trifluoroacetone (TTA) and N, N-Di (1-methyl-heptyl) acetamide (N503) in benzene is studied. By using the usual slope method and equimolar series method the composition of the complex UO2 (TTA)2 · N503 is confirmed. The binary synergic equilibrium constant is determined to be Ig KAB=2.94(average value). The binary synergic thermodynamic parameters are △H = - 29.3kJ, △G=-l6.8kJ,△S=-41.9J/K.