Molecular Dynamics Simulation On Degradation Of Phenol Via Supercritical Water Oxidation

Supercritical water oxidation is a newly-developed, highly-effective technology for the treatment of organic wastewater, which has attracted more and more attention from the researchers because of the unique properties of supercritical water. In this paper, microstructures of the phenol-O₂-H₂O system were investigated by Molecular Dynamics(MD) simulation.The parameters were studied in the simulation of supercritical fluid. Densities of water in supercritical condition, methanol and ethanol at critical point by MD are calculated, and the densities at critical point are 0.3471g/cm³, 0.2945g/cm³ and 0.2976g/cm³ respectively.The results of microstructures investigated by MD indicate that temperature has great effect on the Radial Distribution Function(RDF) of H₂O-phenol and O₂-phenol, and the number of water molecules clustering around the phenol molecule increases with temperature rising and then begin to fluctuate when the temperature reaches 720K, while it decreases with pressure rising and keeps the constant when pressure increase to 27MPa. The simulation results could provide valuable information to guide the practical operation.The reliability of the results of MD was investigated by means of the study of the Partial Molar Volume of ethanol in supercritical CO₂-ethanol system ranging from 308.15K to 328.15K and 11MPa to 15MPa. The results show that the value of experiments and MD are accordant well.