【摘要】 本文以TBP-C₆H₆作为参考溶液,采用等蒸气压法测定了UO₂（NO₃）₂·2TBP-C₆H₆体系中铀萃合物的活度系数。实验结果表明,当浓度较低时,UO₂（NO₃）₂·2TBP与TBP两者的活度系数近乎相等,更多还原

【Abstract】 In the previous paper, the activity coefficient of TBP in the solution of TBP-C6H6 was determined by 32P-labeled TBP distribution method. Based on the above work, the activity coefficient of C6H6 was calculated with Gibbs-Duhem equation by graphical integration method and then the activity coefficient of UO2(NO3)2-2TBP was determined directly by vapor-isopies-tic method. Experimental results showed that at low concen tration,the activity coefficient of UO2(NO3)2-2TBP was approximate to that of TBP(i,e. ,fTBP -fUO2 (NO8)2. 2TBP).In the experiments,reference solution TBP-C6H6 and experimental solution UO2(NO3)2-2TBP-C6H6 were placed in an evacuated container, Thus the solvent benzene evaporated from the solution of- higher vapor pressure and condensed into the solution of lower vapor pressure. While the equilli-brium was attained, the activities of the solvent C8H8 in both solutions were equal to the same. Thus the activity coefficient of the extraction complex UO2(NO3)2-2TBP in the solution of UO2(NO3)2-2TBP-C6H6 could be computed from the activity of the solvent in the reference solution. The solute concentration for each solution was determined by gravimetric method. All the experimental results were used to compute thermodynamig equilibrium constants of extraction reactions,更多还原