Distribution Coefficient Correlations for Nitric Acid, U(VI) and Pu(IV) in Two-Phase System with Aqueous Nitric Acid and 30% Tri-n-Buthylphosphate Solutions

抄録

Distribution coefficient correlations are obtained for nitric acid, U(VI) and Pu(IV) extracted with 30% trin-butylphosphate (TBP) diluted by n-dodecane from aqueous nitric acid solutions. The correlation functions are described as a mathematical model that takes account of activity coefficients expressed by a function of ionic strength. The correlations include the temperature effect on distribution coefficient, and works successfully for the experimental distribution coefficients in the literature within the temperature range of 10 to 70°C. The concentrations of nitric acid, U(VI) and Pu(IV) in a multi-stage extraction experiment previously reported have been simulated well with the new distribution correlations at room and elevated temperatures.