مشخصات پژوهش

Carboxylic acids are commercially compounds and are used in industrially relevant separation processes. They are used in a variety of fields, such as production of nylon, biodegradable plastics, pharmaceuticals and so on [1]. In order to design for the separation, removal and purification of acids, knowledge of the phase equilibra are necessary. Molecular simulation using advanced sampling techniques has become a popular way to study the phase behavior of model systems. Since Gibbs ensemble Monte Carlo (GEMC) method was put forward by A. Z. Panagiotopoullos, it has become one of the most widely used molecular simulation methods due to its strong operability and high accuracy [2]. In this work, configurational- bias Monte Carlo simulations were carried out in the NVT Gibbs ensemble to generate phase equilibrium data for propionic acid systems. The TraPPE-UA force field [3] developed by Kamath and co-works, was used. This force fields was divided in pairwise additive non-bonded interactions and bonded terms for pairs of atoms separated by one, two, or three bonds. The non-bond interactions comprised Lennard-Jones (LJ) 12-6 and Coulomb interactions. The LJ parameters for all interactions are determined with the standard Lorentz-Berthelot combining rules [4]. Monte Carlo simulation carried out with MCCCS-Towhee code in order to calculate the data presented here. Pure component saturated vapor pressure and densities were measured for propionic acid. Results showed good agreement with the experimental data.