Accurate thermophysical property data are vital for effective process design and optimization. Many researchers have used the simultaneous correlation of vapor pressure, heat of vaporization, ideal gas heat capacity, liquid heat capacity, and liquid and vapor densities as a powerful method to model these properties with higher accuracy and thermodynamic consistency. However, achieving such accuracy becomes notably challenging for chemicals that associate. Choices in correlation equations, equations of state and their parameters, and quantum and statistical mechanics methods used in calculation of ideal gas heat capacity significantly impact accuracy. Additionally, the forming and breaking of hydrogen bonds significantly affects these properties, an effect that has been historically overlooked in parameterization of associating equation of state (EoS) models.
In this work, we use acetic acid as a case study to demonstrate that including the contribution of association equilibria to thermophysical properties during EoS parameterization leads to improved parameters and enables thermodynamic consistency in the correlation of the aforementioned properties. By addressing complexities with associating chemicals and offering improved methodologies for simultaneous correlation, this research contributes to improving the reliability of thermophysical property predictions for associating chemicals.
