Prediction of Vapor–Liquid Coexistence Data for p‑Cymene Using Equation of State Methods and Monte Carlo Simulations

A naturally occurring aromatic organic compound, p-cymene, finds applications as reaction intermediate, solvent in production of pharmaceuticals, fragrances, and fine chemicals. The experimental vapor liquid equilibria (VLE) data of p-cymene is available at pressures up to 537.4 kPa. In this study, the thermodynamic properties of p-cymene are determined using structure property correlations combined with equations of state (EoS) and molecular simulation techniques. Two molecular simulation techniques, Gibbs ensemble Monte Carlo (GEMC) and grand canonical-transition matrix Monte Carlo (GC-TMMC) have been employed for prediction of VLE. The estimates of properties, including vapor pressures, heats of vaporization, coexistence densities, and critical properties have been compared with available experimental data. The thermodynamic properties predicted by molecular simulations and also that obtained from Peng–Robinson (PR) and volume translated Peng–Robinson (VTPR) EoS are generally, in broad agreement with the experimental data. Further, GEMC results for coexistence densities and saturation vapor pressures are compared with that from GC-TMMC technique.