Strategy for the management of thermodynamic data with application to practical cases of systems formed by esters and alkanes through experimental information, checking-modeling and simulation

Abstract

In this work, a methodology is established to manage and use, in a more rigorous way, the experimental information that reflects the thermodynamic-mathematical behavior of dissolutions. The management of experimental information is carried out with an application on binaries of esters and alkanes which is useful in any other case. Specifically, for this work a new real database (of several properties under different conditions) is generated for eight binaries formed by four alkanoates, with a carbon number number ≥ 4, and two alkanes C6and C8. A sequence of operations is proposed, ranging from experimentation to simulation, with two highly relevant intermediate stages, modeling verification of the quality of data, whose impact on the simulation is evaluated. The experimental contribution of some properties vE, cPE, hE, gE, gives rise to two very important operations, such as the combined modeling of the properties, taking into account the thermodynamic formalism, and the verification of the vapor-liquid equilibrium (VLE) data. For the latter process, the methodology designed in a previous work (J. Chem. Thermodyn. 2017, 105, 385) is put into practice, as well as a new method, rigorous under a thermodynamic-mathematical point of view, in which the modeling of properties is considered. The binomial model-consistency test is generated as a strategic stage to define the quality of the data. To achieve an accurate modeling in the multifunctional correlation that is proposed, two procedures are adopted: (a), step-by-step (SSO), according to the inverse order of the derivation of the Gibbs function, and another (b), by multiobjective optimization (MOO). The parametrization obtained by the latter is implemented in the commercial software of Aspen-Plus to design a rectification operation to purify the compounds of one of the studied systems, comparing the results with those that the simulator emits with the information estimated by UNIFAC.