The reaction ensemble method for the computer simulation of chemical and phase equilibria. II. The Br2+Cl2+BrCl system

Abstract

The Reaction Ensemble Monte Carlo (REMC) method (W.R. Smith and B. Tr´iska, J. Chem. Phys., 100, 3019 (1994)) is used to study combined reaction and vapor-liquid equilib- rium of the Br2 + Cl2 + BrCl system. The substances are modelled as nonpolar and dipolar two-site Lennard-Jones molecules with Lorentz-Berthelot mixing rules for unlike atoms. No parameters were fitted to any mixture properties in our calculations. The simulated data are compared with experimental results, and with previous simulation data for the mix- ture obtained by an indirect semi-grand ensemble approach. The REMC method eciently calculates the complete phase compositions, whereas only a limited subset is available exper- imentally. The agreement of the simulations with experiment is good. In the course of this work, we used the Gibbs Ensemble Monte Carlo method (which may be regarded as a special case of the REMC method) to calculate the vapor-liquid equilibrium properties of pure BrCl; since this compound is chemically unstable, such data is experimentally inaccessible.