Investigation on isobaric vapor liquid equilibrium for acetic acid + water + (n-propyl acetate or iso-butyl acetate)

Abstract Isobaric vapor–liquid equilibrium (VLE) data for acetic acid + water, acetic acid +  n -propyl acetate, acetic acid +  iso -butyl acetate, acetic acid + water +  n -propyl acetate, acetic acid + water +  iso -butyl acetate are measured at 101.33 kPa with a modified Rose still. The nonideal behavior in vapor phase caused by the association of acetic acid are corrected by the chemical theory and Hayden–O’Connell method, and analyzed by calculating the second virial coefficients and apparent fugacity coefficients. The VLE data for acetic acid + water, acetic acid +  n -propyl acetate, and acetic acid +  iso -butyl acetate are correlated through the NRTL and UNIQUAC models using the nonlinear least square method. The obtained NRTL model parameters are used to predict the ternary VLE data. The ternary predicted values obtained in this way agree well with the experimental values.