CALORIMETRIC STUDIES OF THE SYNERGISTIC EFFECT. THE REACTION OF UO22+, Th4+AND Nd3+TTA COMPLEXES WITH TBP AND TOPO IN BENZENE

Abstract

Titration calorimetry was used to investigate the thermodynamics (ΔG, ΔH, ΔS) of the addition reactions between M(TTA)n(H2O)m (where M = UO2 2+, Th4+, Nd3+) and TBP or TOPO in dry and in water saturated benzene solvent. The adduct species formed were UO2((TTA)2 S, Th(TTA)4 S, and Nd(TTA)3 Sn (n = 1,2).The thermodynamic values complemented by water analysis data, allow evaluation of the relative importance of enthalpic and entropic contributions of ΔG, of the role played by water and of the changes in coordination number which occur during the reactions with the adduct ligands.