An increasingly popular approach when solving the phase and chemical equilibrium problem is to pose it as an optimization problem. However, diiculties are encountered due to the highly nonlinear nature of the models used to represent the behavior of the uids, and because of the existence of multiple local solutions. This work shows how it is possible to guarantee-global solutions for a certain ...

The Gibbs tangent plane criterion has become an important tool in determining the quality of obtained solutions to the phase and chemical equilibrium problem. The ability to determine if a postulated solution is thermodynamically stable with respect to perturbations in any or all of the phases is very useful in the search for the true equilibrium solution. Previous approaches have concentrated ...

The determination region of solubility of methanol with gasoline of high aromatic content was investigated experimentally at temperature of 288.2 K. A type 1 liquid-liquid phase diagram was obtained for this ternary system. These results were correlated simultaneously by the UNIQUAC model. The values of the interaction parameters between each pair of components in the system were obtained f...

In this work, an electrolyte-UNIQUAC model was developed by replacement of Boltzmann weight binary interaction parameters by the nonextensive Tsallis weight. A summation of the long-range electrostatic term (Debye-Huckel equation) and a short-range interaction term were considered in the calculation of thermodynamic properties. A framework proposed by Chen and co-workers was employed for the de...

Isobaric vapor–liquid equilibrium (VLE) data for 2-propanol + 1-butanol, 2-propanol + 1-pentanol, 1butanol + 1-pentanol and 2-propanol + 1-butanol + 1-pentanol were measured at 101.3 kPa by using an improved Rose still. All the binary VLE data have passed the traditional area test proposed by Herington. The interaction parameters for the Wilson, NRTL and UNIQUAC equations were determined by reg...

The nitrocellulose based materials are degraded in a natural way during their storage; the processes of degradation are accelerated when the temperature or the humidity increases. To prevent this decomposition, these materials include in their composition stabilising agents which retain the nitro groups and avoid the autocatalytic degradation of nitrocellulose. The aim of the present work is to...

The catalytic-distillation process for the production of t-amyl-methyl-ether (TAME) from methanol and isoamylenes was simulated by developing the process model as a combination of unit operations from HYSYS operations palette. Geometrical characteristics of catalytic-distillation column are those of an industrial pilot plant and the results of simulation were compared with experimental data. T...