Purification Of Hydrogenated Toluene And The Research On Vapor-liquid Equilibria By Molecular Simulation

First in this paper is the purification of hydrogenated coking toluene by normaldistillation. A two-column continuous distillation flowsheet was adopted. The processwas simulated through Aspen Plus software by NRTL thermodynamic method tooptimize the operational parameters and get the best ones. Then a small-styleexperiment was conducted accordingly, of which the outcome matched well with thesimulation one, and the high pure toluene product was got finally.Then by reference of the components in the hydrogenated coking toluene,molecular simulation was conducted for pure and binary vapor-liquid equilibria ofsome alkanes and aromatic hydrocarbons. The simulation was conducted under Gibbsensemble by Monte Carlo methods through MCCCS Towhee software package. TheTraPPE-UA force field was used. In the simulation of pure components underNVT-Gibbs ensemble, the orthobaric density was got to represent the pure substance’sequilibrium. Then simulation of binary mixtures was conducted under NpT-Gibbsensemble to get the P-x-y or T-x-y equilibria data. By comparing the simulationoutcome with the literature data, the validation of the method for predicting phaseequilibria of pure and binary system can be estimated.Good results was achieved for the pure and binary components simulations thispaper. By observing the vapor-liquid equilibria diagrams, certain deviations can bedetected between simulation results and literature data in some points, but overall,they made a good agreement, which validated the accuracy and reliability of the forcefield and simulation methods that were used in the simulation of this paper.