Application of ion-based ePC-SAFT in prediction of density of aqueous electrolyte solutions

Abstract

An electrolyte equation of state based on PC-SAFT in conjunction with Debye-Huckel term has been utilized for calculating the density of aqueous electrolyte solutions using two different strategies. In the first manner, the association interaction between water and ions does not consider, while in the second strategy, the associative hydrogen-bonding behavior between ions and water are implemented. Using the experimental densities of 80 binary aqueous electrolyte solutions including 31 common ions, ion parameters have been optimized by a global optimization method. The corresponding results of both strategies are presented and compared with the experimental density of single and mixed electrolyte solutions up to 373.15K. Furthermore, the estimated individual ion parameters have been reasonably extended to predict different properties of multicomponent electrolyte solutions. Finally, by comparing the obtained average relative deviations of densities for binary solutions, it can be observed that the density is satisfactorily calculated with considering ions as associating compounds (Overall ARD~0.8).