Experimental isobaric vapour-liquid equilibrium data for the binary system (N, N-dimethyl acetamide + dimethyl sulfoxide) and the quaternary system (sec-butyl acetate + sec-butyl alcohol + N, N-dimethyl acetamide + dimethyl sulfoxide) at 101.3 kPa

• The mixed solvent DMAC + DMSO can eliminate the pseudo-azeotrope of SBAC and SBA. Isobaric vapour-liquid equilibrium (VLE) data for the binary system of { N , N -dimethyl acetamide (DMAC) + dimethyl sulfoxide (DMSO)} and the quaternary system of { sec -butyl acetate (SBAC) + sec -butyl alcohol (SBA) + DMAC + DMSO} were measured at 101.3 kPa using a modified Othmer still. The thermodynamic consistency test for the binary experimental data was checked by Van Ness point test. The experimental VLE data of the binary system were correlated with Wilson, NRTL and UNIQUAC activity coefficient models. The binary and quaternary VLE data predicted by the binary interaction parameters agreed well with the experimental data. And the mixed solvent (DMAC + DMSO) can eliminate the pseudo-azeotrope of SBAC and SBA. Thus the mixture of (DMAC + DMSO) is a potential extractive solvent in the separation of the pseudo-azeotrope of SBAC and SBA by extractive distillation. [ABSTRACT FROM AUTHOR]