Phase behavior of water + hydrocarbon binary systems by using multi-fluid nonrandom lattice hydrogen bonding theory

A simple lattice hydrogen bonding theory for water+hydrocarbon systems is formulated. The theory is derived under the assumption that the intermolecular forces are divided into physical and chemical parts. Veytsman’s statistics for the hydrogen bonding (HB) contribution is combined with the multi-fluid nonrandom lattice–fluid (MF-NLF) model previously developed by the present authors. The present MF-NLF-HB theory contains two molecular parameters representing molecular size and energy, and one additional interaction parameter for binary systems. The model is applied to quantitatively describe the thermodynamic properties of complex binary systems containing water and hydrocarbon.