Journal of Petroleum & Environmental Biotechnology

Modeling of phase equilibria at high pressure using different cubic equations of state-mixing rule combinations

5^th World Congress on Petrochemistry and Chemical Engineering

December 05-07, 2016 Phoenix, USA

Meniai Abdeslam-Hassen

University Constantine 3, Algeria

Posters & Accepted Abstracts: J Pet Environ Biotechnol

Abstract:

Generally the experimental measurement of phase equilibria data at high pressure is complex, difficult, expensive and time consuming; hence there is need for reliable equations of state. A great number of equation of states are known but the other major difficulty is the choice of the most adequate combination of an equation of state (EOS) and a mixing rule (MR), for a given system at defined operating conditions. Consequently, to illustrate this crucial point, the present work considered the modeling of the solubility of chosen pharmaceutical compounds in supercritical carbon dioxide using known cubic equations of state in combination with four different mixing rules, namely, that of van der Waals, Panagiotopoulos and Reid, Wong-Sandler and Kwak and Mansoori mixing rules. A priori of the required physicochemical and critical properties of the considered compounds were predicted using well known methods based on the group contribution concept. The interaction parameters kij was obtained from experimental data available in the literature and involving the chosen pharmaceutical compounds, by the optimization of a well-defined objective function using the Nelder-Mead version of the simplex technique. For most systems, a quite good agreement between the calculated and experimental data was obtained for few EOS-MR combinations only, confirming that the accuracy of the results depends upon the choice of the combination. Finally the model of the best EOS-MR combination can be used to perform computer experiments according to various specific applications like for instance crystallization process using supercritical fluid where thermodynamics and phase equilibrium are the key matters.

Biography :

Email: meniai@yahoo.fr