ParamIni_LL_NRTL: Graphical User Interface (GUI) for the Selection of NRTL Initial Parameters for the Correlation of Ternary Liquid-Liquid Equilibrium Data (Type I, II, III and 0 (LL island), i.e. with 1, 2, 3 or 0 binary pairs partially miscible)

Abstract

The correlation of liquid-liquid equilibrium data is still currently a problem not fully resolved, especially for complex systems such as, those involving ionic liquid, where the high nonlinearity and non-convexity of the equations involved produce convergence problems, with a strong dependence on the initialization values used of the obtained solution. To avoid this situation, for the NRTL model, we have analyzed more than 200 LLE ternary systems (including type I, II, III and 0 or island, following the Treybal classification, Figure 1) in order to obtain a good representation of the different possible binodal curves and tie triangles that this model can reproduce satisfactorily, in a wide enough interval of values of the different parameters (taui,j, taui,j). All these systems have been parametrized regarding the main characteristics of the corresponding LLE, such as the number of binary subsystems partially miscible, the size and middle point of the binary tie-lines, the slope of the tie-lines, the location of the plate point, etc. With this parametrization, we have created a database and a new graphical user interface, GUI, that allows loading a set of liquid-liquid experimental data to obtain, using optimization algorithms and machine learning techniques, a consistent set of initial NRTL parameters that predicts a parametrized LLE near the experimental one. This set of parameters can be used now in any correlation data algorithm (using the corresponding equilibrium condition: isoactivity, minimum of the global Gibbs energy of mixing, or the Gibbs energy of mixing minor common tangent plane) to obtain the final rigorous solution. We believe that the present work can help researchers, professionals and students, in the task of correlating experimental liquid-liquid equilibrium data, in order to obtain consistent binary interaction parameters, taking into account that the correct calculation of the phase equilibrium is a key point in the optimal (efficient and sustainable) design of the corresponding processes and equipment. Related references: *Should we trust all the published LLE correlation parameters in phase equilibria? Necessity of their Assessment Prior to Publication. Fluid Phase Equilibria. 2017, 433, 243-252 (http://dx.doi.org/10.1016/j.fluid.2016.11.009). *GE Models and Algorithms for Condensed Phase Equilibrium Data Regression in Ternary Systems: Limitations and Proposals. The Open Thermodynamics Journal. 2011, 5, (Suppl 1-M5) 48-62 (http://dx.doi.org/10.2174/1874396X01105010048). * Checking Liquid-Liquid Critical Point Conditions and their Application in Ternary Systems. Industrial & Engineering Chemistry Research. 2012, 51(13), 5098-5102 (http://dx.doi.org/10.1021/ie202793r). *LLE data correlation using NRTL model for different types of binary systems: UCST, LCST and closed miscibility loops. Industrial & Engineering Chemistry Research. 2020, 59(17), 8469-8479 (https://doi.org/10.1021/acs.iecr.0c00141). * GMcal_TieLinesLL: Graphical User Interface (GUI) for Topological Analysis of Calculated GM Surfaces and Curves, including Tie-Lines, Hessian Matrix, Spinodal Curve, Plait Point Location, Miscibility Boundaries, etc. for Binary and Ternary Liquid-Liquid Equilibrium (LLE) Data. RUA 2015-2022. http://hdl.handle.net/10045/51725. *GMcal_TieLinesVL: Graphical User Interface (GUI) for the Topological Analysis of Experimental and Calculated GM Functions for Binary and Ternary (isobaric or isothermal) Vapor-Liquid Equilibrium (VLE) Data (including Tie-Lines, Derivatives, Distillation Boundaries, etc.). RUA 2022. http://hdl.handle.net/10045/122857. * Boundaries_LL_NRTL Graphical User Interface (GUI) for the Characterization of the NRTL model: Binary Spinodal Surfaces (in the tau(i,j)-tau(j,i)-xi space), LLE Maps and Miscibility Boundaries. RUA 2022 (http://hdl.handle.net/10045/121471). * What does the NRTL model look like? Determination of boundaries for different fluid phase equilibrium regions. AIChE Journal. 2022, e17805 (https://dx.doi.org/10.1002/aic.17805).