Vapour-Liquid Equilibrium of by-Products n-Alcohols and 1,3-Propanediol from Polyol Production

Abstract

A new method for collecting vapour-liquid equilibrium data for binary mixtures is proposed in this work. A modified differential scanning calorimetry technique was used by evaluating the sample temperature instead of the heat flow. This method was tested on three well known systems and the results from this technique agreed very well with published data. This new method was then used for determining the vapour-liquid equilibrium behaviour of binary mixtures of 1-hexanol, 1-heptanol, 1-nonanol and 1,3-propanediol. Correlation of the experimental data was done using both activity coefficient and equation of state models. An azeotrope was found in the 1-nonanol and 1,3-propanediol binary system but not for the other binary pairs. Therefore, an alternative for conventional distillation should be considered in order to separate these two main components.