Abstract
Hydration of tributyl phosphate (TBP) at concentrations up to 0.3mol dm-3 in dodecane (8.1 vol% TBP) was examined at 298K. Water extraction into TBP-dodecane solutions was measured and the data were analyzed as a function of TBP concentration in the organic phase and of water activity in the aqueous phase. The data analyses showed the presence of two TBP-water complexes in the organic phase. When the TBP concentration in the organic phase is low enough, only a TBP hydrate of TBP•H2O is formed. However, at high TBP concentrations, this hydrate dimerizes to form (TBP)2(H2O)2. The TBP-water stoichiometry taking account of these two complexes well explained the experimental data in the TBP concentration range examined.
