Vapour–liquid equilibrium and azeotropic behaviour of 1,2-dichloroethane with isomeric butanols

A dynamic recirculating still was employed to measure isobaric vapour–liquid equilibrium at the pressures of 40.0, 66.6 and 101.3 kPa for the binary systems 1,2-dichloroethane with 1-butanol, 2-butanol, 2-methyl-1-propanol and 2-methyl-2-propanol. The experimental data were tested for thermodynamic consistency, the calculated activity coefficients have been correlated using Wilson, NRTL and UNIQUAC equations. The mixtures containing 2-butanol, 2-methyl-1-propanol and 2-methyl-2-propanol show minimum temperature azeotropes. Predictions with the UNIFAC method were also obtained.