Modeling of Gas Solubility in Hydrocarbons Using the Perturbed-Chain Statistical Associating Fluid Theory Equation of State

Fitted functions that correlate binary interaction parameters (BIP) for the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state (EoS) with the carbon number of n-alkanes were established for gas solubility in n-alkanes using solubility data of gases in a few selected n-alkanes typically with 10–28 carbon atoms. Data screening was made to ensure accuracy and consistency of data used for parametrization and validation. The PC-SAFT EoS using the BIPs by the established fitted functions was evaluated against experimental data. It was found that the PC-SAFT EoS is quantitatively accurate for the entire homologous series of n-alkanes, regardless of whether the data of n-alkanes were used in the parametrization. It was shown that the PC-SAFT EoS successfully reproduces the two types of the temperature dependence of gas solubility: (1) gas solubility decreases with an increasing temperature and then increases; (2) gas solubility always increases with an increasing temperature. In part...