ACEOS – The additive and constitutive equation of state in the n-alkane homologous series

Abstract

The critical volumeVc, the relation between the critical temperature and the pressure Tc / Pc and the product PcVc2 depend linearly on the number of carbons in a homologous series as a consequence of the theory of corresponding states. This suggests that additive and constitutive properties are suitable for the construction of equations of state. In this article, an equation of state of Soave–Redlich–Kwong type is proposed: an additive and constitutive equation of state because it contains among its constitutive parameters the parachor (℘ch) and the molar refraction (Rm). The homologous series of the n-alkanes is used to illustrate the applicability of the proposed equation.

Keywords

• Homologous family of n-alkanes
• Linear equation
• Group contributions
• Cubic equations of state
• Parachor
• Molar refraction