Gas solubility in hydrocarbons—a SAFT-based approach

Solubility of methane, ethane, carbon monoxide and hydrogen in the linear alkane and 1-alkene homologous series is modeled using the Statistical Associating Fluid Theory (SAFT) equation of state (EOS) with a perturbed chain dispersion term (subsequently referred to as PC-SAFT). The pure component PC-SAFT parameters were obtained from the literature or, in the case of the higher alkenes (up to tetradecene), were generated by correlating vapor pressure and liquid density data. Pure component parameters for hydrogen were regressed by fitting to mixture data at high temperatures and pressures. PC-SAFT is seen to correctly model solubility trends with temperature and increasing carbon number of the solvent. A single binary interaction parameter (kij) that is independent of carbon number and in many cases temperature applies to each gas/homologous series pair.