On the compatibility between vapor pressure data and the critical constants: Use of the van der Waals family of cubic equations of state to study the cases of 2-methoxyethanol and 2-ethoxyethanol

Abstract

The performance of five cubic equations of state (EOSs) for the correlation of vapor–pressure data of 2-methoxyethanol and 2-ethoxyethanol are compared. The cubic EOSs considered are the van der Waals EOS, modified with Soave's approach (MvdW), the Soave–Redlich–Kwong (SRK), the Peng–Robinson (PR), and the two versions of the Peng–Robinson–Stryjek–Vera EOSs: PRSV and PRSV2. Three sets of critical constants for 2-methoxyethanol are considered and new acentric factor is proposed for this compound. New critical constants and acentric factor for 2-ethoxyethanol are proposed. Pure compound parameters for the PRSV and the PRSV2 EOSs for 2-methoxyethanol and 2-ethoxyethanol are evaluated using a genetic algorithm (GA) optimization technique. The results show the importance of using compatible information in vapor liquid equilibrium studies.