Chemical-Phase Equilibrium of CO–CO2–H2–CH3OH–DME–H2O Mixtures in C–H–O Atom-Mol Fraction Space Using Gibbs Free Energy Minimization

Abstract

This work employs Gibbs free energy minimization to carry out reaction and phase equilibrium analysis for a CO–CO2–H2–CH3OH–DME–H2O mixture, in a manner that enables a compact representation of the mixture’s feed composition in terms of the feed’s C–H–O atom-mol fractions. The concept of the Atom Species Attainable Region (ASAR) is formally defined, and propositions are developed that identify ASAR in C–H–O atom-mol fraction space for feed compositions consisting of either all six or four of the six aforementioned species. Then, Gibbs free energy minimization is carried out for a broad collection of ASAR points and a wide range of temperatures and pressures, aiming to identify conditions favoring DME production. The results of this comprehensive equilibrium analysis are then presented, and conclusions are drawn.