The vapor pressures of (4-ethylmorpholine + water), (1,2-dimethylisopropylamine + water), (N,N-dimetylethanolamine + water) binary mixtures, and of pure 4-ethylmorpholine, 1,2-dimethylisopropylamine and N, N-dimethylethanolamine components were measured by means of two static devices at temperatures between {273 (or 283) and 333 (or 363)} K. The data were correlated with the Antoine equation. From these data excess Gibbs functions (G(E)) were calculated for several constant temperatures and fitted to a fourth-order Redlich-Kister equation using the Barker's method. The (4-ethylmorpholine + water), and (1,2-dimethylisopropylamine + water) binary systems show positive azeotropic behavior. The aqueous solutions of 4-ethylmorpholine and 1,2-dimethylisopropylamine exhibit positive deviations in G(E) for all investigated temperatures over the whole composition, where the aqueous solution of N, N-dimetyhlethanolamine show a S shape for G(E) for (273.15 < T < 313.15) K. Additionally, the Wilson, NRTL or UNIQUAC models have been used and quite good results were obtained in the prediction of the total pressure. (C) 2013 Elsevier Ltd. All rights reserved.