Isobaric vapor-liquid equilibrium (VLE) data were measured for the binary systems sec-butyl alcohol +N, N-dimethyl acetamide (DMAC), sec-butyl acetate + DMAC and the ternary system sec-butyl alcohol + sec-butyl acetate + DMAC at 101.3 kPa using a vapor-liquid equilibrium still. The thermodynamic consistency test for the binary experimental data was made by Herington method and McDermott-Ellis method. And the thermodynamic consistency test for the ternary experimental data was made by McDermott-Ellis method. The binary VLE data were correlated with the NRTL, Wilson and UNIQUAC activity coefficient models. The obtained binary interaction parameters were used to predict the binary and ternary VLE data. The results indicate that the calculated values of vapor phase mole fraction and boiling temperature by the NRTL, Wilson and UNIQUAC models agree well with the experimental data. And the binary pseudo-azeotrope of sec-butyl alcohol and sec-butyl acetate was eliminated when the mass ratio of DMAC to the pseudo-azeotrope mixture is 6:5. Thus, DMAC is an appropriate solvent for separation of the mixture of sec-butyl alcohol and sec-butyl acetate in extractive distillation. (C) 2015 Elsevier B.V. All rights reserved.