A new model combining Helmholtz energy equations of state with excess Gibbs energy models to describe reactive mixtures. (28th April 2022)

• Record Type: Journal Article
• Authors: Neumann, Tobias; Poplsteinova Jakobsen, Jana; Thol, Monika; Span, Roland
• Is Part Of: Chemical engineering science. Volume 252(2022)
• Publication Date: 2022-04-28
• Subjects: Equation of state -- Phase and chemical equilibrium -- e-NRTL model -- Helmholtz energy -- Excess Gibbs energy -- Thermodynamic properties; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2021.117261
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: Combination of Helmholtz energy and excess Gibbs energy. Simultaneous calculation of phase and chemical equilibrium with one equation of state. Description of all thermodynamic properties with one model in all fluid states. Validation and analysis with vapor–liquid equilibrium, density, and speciation data. Abstract: A new model is presented, which consistently combines equations of state in terms of the Helmholtz energy with excess Gibbs-energy models. It enables the description of reactive mixtures by solving the phase and chemical equilibrium based on Helmholtz-energy equations of state, that are commonly used to describe non-reactive systems. The consistent calculation of all thermodynamic properties in the complete fluid region, including gas, liquid, and supercritical states as well as phase equilibria, is possible. The fundamental property is the Helmholtz energy with the independent variables temperature, density, and composition. The new model reproduces well experimental vapor–liquid equilibrium, homogeneous density, and speciation data of the binary system of monoethanolamine + carbon dioxide as well as of the ternary system of water + monoethanolamine + carbon dioxide.