Molecular simulation of multicomponent reaction and phase equilibria in MTBE ternary system

Abstract

Reaction and phase equilibria in the isobutene + methanol + MTBE ternary system were studied using the reaction‐ensemble Monte Carlo (REMC) simulation method. The system was modeled at the molecular level by an OPLS force field. No adjustable binary cross‐interaction parameters or mixture data of any kind were used in the simulation model, and only vapor‐pressure data for the pure components was required as input. The REMC method also computes excess internal energies and molar volumes as a biproduct of the simulations. Both the nonreacting and reacting ternary systems were considered over the temperature range of practical interest at 5 bar. Results are compared with the calculations using two conventional thermodynamic approaches: the Wilson and UNIFAC free‐energy models for the liquid phase, together with a truncated virial equation of state for the gas phase in both cases. Computer simulation results were similar to those of the thermodynamic approaches, and they are arguably more accurate.