VAPOR-LIQUID-EQUILIBRIUM OF THE ETHANOL PROPANAL SYSTEM

A Gibbs-Van Ness type apparatus for total vapour-pressure measurements of binary mixtures has been developed. Vapour-liquid equilibrium data for the ethanol-cyclohexane system at 298.15 K have been obtained and compared with previous literature data. Data reduction has been carri ed out by a modified Barker's method using a Pade approximant to descr ibe to excess Gibbs energy. The vapour-liquid equilibrium data for the ethanol-propanal systems have been measured over the whole concentrat ion range at 298.15, 308.15 and 318.15 K. These mixtures show negative deviations from ideality. The calculated values for the excess functi ons are large and negative, and the calculated values for the concentr ation-concentration correlation function are lower than ideal values. This experimental behaviour is analysed in terms of the UNIQUAC model and several versions of the UNIFAC model.