Molecular simulation of the vapor–liquid phase behavior of cyanides and their binary mixtures

The vapor–liquid phase behavior of binary mixtures containing cyanogen, cyanogen chloride, hydrogen cyanide and acetonitrile is predicted by molecular simulation and compared to experimental data as well as the Peng–Robinson equation of state. Two new molecular force field models are presented for cyanogen and cyanogen chloride, molecular models for the other compounds are taken from preceding work. The parametrization of the present classical molecular interaction models is carried out on the basis of quantum chemical calculations and subsequent fitting to experimental vapor pressure and saturated liquid density data. To validate the present molecular models, vapor–liquid equilibria for the pure cyanides and 14 binary mixtures containing cyanides are calculated and compared with the available experimental data and the Peng–Robinson equation of state. In general, the simulation results are in good agreement with the experimental data.