Determination of activity coefficients and diffusion coefficients of LiClO4 in ethylene carbonate +water mixtures based on potentiometric measurements at T=(298.2, 308.2, and 318.2) K

Abstract

ABSTRACT We studied the thermodynamic properties of the lithium perchlorate (LiClO4) + ethylene carbonate (EC) +water ternary system by using cell potential measurements. Thermodynamic properties reported were obtained using the electrochemical cell: Li-ISE|LiClO4(m)|ClO4-ISE in a variety of mixed solvent systems containing 0, 10, 20 and 30% mass fractions of ethylene carbonate in water + EC mixtures (wEC/wmixture% = 0, 10, 20 and 30) on the wide range of ionic strength from 0.0090 to 2.4900 mol.kg−1 at T = (298.2, 308.2 and 318.2) K. The obtained results were analysed using Extended Debye-Huckel equation and Pitzer model. The values of Pitzer ion-interaction parameters β(0), β(1) and Cϕ were used to drive the values of thermodynamic properties such as the excess Gibbs free energy, the solvent activity, mean activity coefficients, the osmotic coefficients and diffusion coefficients for this system.