Modeling aqueous multivalent polyelectrolytes systems with polyelectrolyte NRTL model

Thermodynamic modeling of aqueous polyelectrolyte systems is of great interest in many industrial applications and biological systems. Recently a Polyelectrolyte Nonrandom Two-Liquid activity coefficient model was proposed for aqueous monovalent polyelectrolyte systems. Integrating Manning's counterion condensation theory, Pitzer-Debye-Hückel theory, and electrolyte Nonrandom Two-Liquid theory, the model accounts for the solution nonideality derived from long-range electrostatic polyion-ion and ion-ion interactions as well as short-range van der Waals molecule–molecule, molecule-ion, and ion-ion interactions. This work extends the model for aqueous multivalent polyelectrolyte systems and shows satisfactory agreement between the model results and the available literature data on thermodynamic properties of varieties of multivalent polyelectrolyte systems.