Theoretical calculation of activity coefficients of liquid mixtures

Abstract

Significant structure theory was applied to some liquid mixture systems ranging from simple monatomic molecule systems to polyatomic molecule systems and the activity coefficients of the liquid mixture systems were calculated over whole mole fraction. The activity coefficients of the solutions such as monatomic molecule systems(Ar - Kr, Kr - Xe) and diatomic molecule systems ($Ar - O_2,\; N_2 - CO$) and $CH_4 - Kr$ systems were calculated successfully only with the $\delta$ Es correction parameter. For other systems such as $Ar - N_2,\; O_2 - N_2$ and $CH_4 - C_3H_8$, aditional correction parameters $\delta$v and $\delta$n were necessary. For methane, hindered rotational partition function was used and it was assumed to be dependent on mole fraction. The parameters of liquid propane were determined by Seoule Technique. Some discussions on one fluid model and two fluid model were given also.