The hydration and dimerization of N,N-bis(2-ethylhexyl) hexanamide (BE
HHA) in dodecane were studied on the basis of the water distribution b
etween aqueous solutions and dodecane. The data obtained at 298 K were
analyzed as functions of the amide concentration in the organic phase
and the water activity in the aqueous phase. When the amide was monom
eric in the organic phase, only a monohydrate was formed. At high amid
e concentrations in the organic phase, dimerization of the monohydrate
occurred and (BEHHA)(2)(H2O)(2) was formed. No other dimer hydrates w
ere found in the organic phase. The results were compared with those o
f tributyl phosphate (TBP). The stoichiometry between BEHHA and water
was investigated from low to very high amide concentrations in dodecan
e. The change in the activity coefficient for an amide contained in an
inert solvent at high concentrations was also examined.