Modeling Phase Equilibria of Ethers and Alcohols with GCA-EOS for Assessing the Coblending of Advanced Biofuels

Abstract

In this work, we extend the Group Contribution with Association Equation of State (GCA-EOS) to model the phase behavior of mixtures comprising ethers and alcohols. The model parametrization was done using few binary vapor-liquid equilibrium data sets of linear monoethers. We also model the behavior of branched ethers, traditionally used as fuel additives, as well as that of polyethers, which are nowadays being proposed as potential biofuels. Therefore, we investigate not only the phase equilibria but also excess enthalpies of these three types of ethers in mixtures with alcohols. Finally, we show that the GCA-EOS is able to predict the phase behavior of polyethers, as well as that of branched ethers, using a group contribution approach. This work is part of a broader project for the development of a robust and predictive thermodynamic model for process and product design in the context of biomass valorization. In addition, the parametrization reported here aims to provide a reliable framework specific for the description of thermodynamic properties of biofuel blends.