Molecular Simulation Of Solubility For Diphenyl Carbonate Related Synthesis Systems

Diphenyl carbonate(DPC) is an important aromatic carbonate due to its wide use in chemistry. Researches on the phase equilibria of related synthesized systems of DPC can provide the bases for product separation. Carbon monoxide, ethanol and phenol are among the necessary reactants and solvents of the synthesis of DPC, and are chosen as the research objects in this paper. Related phase equilibria of such systems in different temperature and pressure ranges were studied through the newly developed molecular simulation method.Vapor-liquid equilibrium(VLE) properties of pure ethanol was simulated firstly as a test of the chosen OPLS-UA force field at 295.15-359.15 K. The force field proved to be reliable. The following gas-liquid equilibrium(GLE) property of carbon monoxide-ethanol system at 298-323 K and 1-7MPa was simulated in two methods, one was Widom insertion method, the other was Gibbs ensemble Monte Carlo(GEMC) method. Results of both methods show good agreement with experimental data.A rigid OPLS-UA force field for phenol was created in the simulation of GLE property of carbon monoxide-phenol system. Density of phenol at 333.15-523.15 K was calculated with the rigid force field. The simulated densities are found to be quite satisfactory, with a lowest relative deviation of 0.7%. The GLE property of carbon monoxide-phenol was simulated in GEMC method at 323.15-333.15 K and 4.01-8.09 MPa. At last, solubility of carbon monoxide in the mixed phenol-ethanol solvents were calculated at 303.15 K, 2.93-7.01 MPa. Mole fractions of phenol in the mixed solvents were set 0.2, 0.39 and 0.6167, respectively.Simulation results in this paper are in agreement with experimental data, proving that molecular simulation can perform well in calculating gas-liquid equilibria of DPC related synthesis systems. Results indicate that solubility of carbon monoxide in ethanol, phenol and the mixed phenol-ethanol solvents increases with pressure. The relationship between mole fraction of carbon monoxide and pressure in all these systems can be described by Henry’s law. Temperature has a positive effect on the solubility of carbon monoxide in phenol, but little influence on that in ethanol. When it comes to the mixed phenol-ethanol solvents, the the solubility of carbon monoxide shows a decrease as the mole fraction of phenol increases in the mixed solvents.