Measurement and Modelling of Excess Molar Volume and Excess Enthalpy of n-tridecane or n-tetradecanewithdecalin By Application of PFP Theory

Abstract

The experimental measurement of density and enthalpy of mixture for two binary liquid mixtures of n-tridecane or n-tetradecane with decalin was reported in this paper. The measurements were conducted at a temperature range of 293.15 to 323.15K and at 303.15K using calorimeter C80. The mixtures were analyzed at various proportions, including the entire composition range and infinitely diluted. The excess molar volume (VE) and excess molar enthalpy (HE) of mixtures were calculated and fitted using the Redlich-Kister equation. The paper observed the expansion phenomenon for the VE at all temperatures, including over the entire composition range and infinitely diluted. Additionally, the HE exhibited endothermic behavior at the studied temperature range and composition range. The Prigogine-Flory-Patterson (PFP) theory was utilized to predict both thermodynamic properties, namely the VE and HE. The results obtained using the PFP theory were compared with those obtained using the Treszczanowicz and Benson association (TB) model for VE and with the NRTL, Wilson, and Flory models for HE. The PFP model, which employed a single fitted parameter to describe VE, demonstrated satisfactory performance in predicting VE. Conversely, the Treszczanowicz and Benson association (TB) model yielded relatively poor results in fitting VE. However, the NRTL, Wilson, PFP, and Flory models exhibited good performance in predicting HE.