Activity coefficients determination and thermodynamic modeling of (NaCl + Na2HCit + glucose + H2O) system at T = (298.2 and 308.2) K

Abstract In this work, the thermodynamic properties of the electrolyte mixture (NaCl + Na 2 HCit + glucose + H 2 O) using the potentiometric method, were reported. The potentiometric measurements were carried out on the galvanic cells over total ionic strengths from 0.05 to 4.00 mol·kg − 1 . Different series of the salt molal ratios r (r = m NaCl /m Na2HCit  = 1, 2.5, 5.0, 7.5, 10.0) and pure NaCl and Na 2 HCit in mixed solvent system containing 10% mass fraction of glucose were used for the measurement at T = (298.2 and 308.2) K and P = 0.1 MPa. Pitzer ion-interaction model was used to correlate the experimental data. The mixing parameters obtained (θ ClHCit and ψ NaClHCit ) were used to calculate the values of the mean activity coefficients of Na 2 HCit, the osmotic coefficients, solvent activity and the excess Gibbs free energies for the whole series of the studied mixed electrolyte system.