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Thermodynamic study of binary systems containing sulphur dioxide: Measurements and molecular modelling

E El Ahmara, B Creton, A Valtz, C Coquelet, V Lachet, D Richon, P Ungerer
Fluid Phase Equilibria 304, 21 (2011)

In the present work, we report isothermal vapour–liquid equilibrium data for two binarysystems: nitrogen–sulphur dioxide and oxygen–sulphur dioxide at four temperatures (323.15, 343.15, 373.15, and 413.15 K) and pressures up to 85 MPa. These data were simultaneously obtained from experimental measurements and molecular simulations. The compositions of coexisting phases were experimentally determined using an apparatus based on the “static-analytic” method. At the same time, Gibbs ensemble Monte Carlo (MC) simulations were performed on these binary mixtures, using forcefields based on pure component properties. An original forcefield is proposed for sulphur dioxide molecule, involving three Lennard–Jones centres and three electrostatic charges. The experimental and simulation results appear in good agreement, allowing reliable and accurate predictions at higher pressures with molecular simulations.