ThermoData Engine (TDE) Software Implementation of the Dynamic Data Evaluation Concept. 7. Ternary Mixtures

Abstract

ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for ternary chemical systems. The method involves construction of Redlich-Kister type equations for individual properties (excess volume, thermal conductivity, viscosity, surface tension, and excess enthalpy) and activity coefficient models for phase equilibrium properties (vapor-liquid and liquid-liquid equilibrium). Constructed ternary models are based on those for the three pure component and three binary subsystems evaluated on demand through the TDE software algorithms. All models are described in detail, and extensions to the class structure of the program are provided. Reliable evaluation of properties for the binary subsystems is essential for successful property evaluations for ternary systems, and algorithms are described to aid appropriate parameter selection and fitting for the implemented activity coefficient models (NRTL, Wilson, Van Laar, Redlich-Kister, and UNIQUAC). Two activity coefficient models based on group contributions (original UNIFAC and NIST-KT-UNIFAC) are also implemented. Novel features of the user interface are shown, and directions for future enhancements are outlined.

ThermoData Engine (TDE): Software Implementation of the Dynamic Data Evaluation Concept. 8. Properties of Material Streams and Solvent Design

“…This approach is analogous to that used previously for binary mixtures (version 3) 3 and ternary mixtures (version 6). 7 The Gibbs Phase Rule specifies the maximum number of phases that may be present and the number of independent state variables required to fully define a property for a system with a given number of components (chemical compounds). These restrictions limit the number of possible system types, but the number of potential phase and variable combinations is very large for multicomponent mixtures involving more than two components.…”

“…Equations used and the fitting procedures were described, 3 and those procedures were used here, except for viscosities, where a newer formulation was used. 7 Step 5: Creation of Single-Property Models for Material Streams. The portions of the algorithm specifically related to formulation of models for material streams are shown within the dotted rectangles in Figure 1.…”

“…3 Procedures for automatic evaluation have since been improved substantially, and complete details of the procedures were reported with our description of property evaluations for ternary systems. 7 Step 7: Creation of AC Models for a Material Stream. Creation of an AC model for a material stream requires successful model creation for all binary subsystems (step 6, Figure 1).…”

“…7 TDE is used in a multitude of applications ranging from data quality assurance, 17 to validation of new experimental data, 18 to chemical process and product design. 19,20 It is also a core component in implementation of the concept of Global Information Systems in Science with application to the field of thermodynamics.…”

“…19,20 It is also a core component in implementation of the concept of Global Information Systems in Science with application to the field of thermodynamics. 21 Other recent additions include a vapor−liquid equilibrium (VLE) data modeling test that complements consistency tests implemented previously for low-pressure/subcritical VLE data, 15,22 as well as addition of the NIST-KT-UNIFAC prediction method 23 for VLE data, which was developed based on data quality factors (i.e., data set weighting factors) described previously 22 and automatic decomposition of molecular structures into KT-UNIFAC groups and subgroups. 24 The present article describes extension of TDE (version 7, released in 2012) 25 for evaluation of properties of material streams (defined as a mixture with any number of components and specified overall composition).…”