Solubility of potassium dihydrogen phosphate in aqueous solutions of acetone, ethyl acetate, and thiourea from T = (298.15–313.15) K

The solubility values of potassium dihydrogen phosphate in binary mixtures of acetone + water, ethyl acetate + water, and thiourea + water were measured using a gravimetric method in a temperature range of (298.15–313.15) K. All results from these measurements were correlated using a simplified Pitzer approach. The relationship obtained between the Pitzer parameter concerning the interactions of ions and non-electrolyte molecules (=λ) and temperature applies well to the solubility data in the ternary systems tested. The values of λ parameter were also compared to those obtained in the literature (Y. Enqvist, J. Partanen, M. Louhi-Kultanen, J. Kallas, Trans IChemE A, 81 (2003) 1355–1362) for systems urea + water, ethanol + water, and 1-propanol + water.

► New KH2PO4 solubility data in aqueous acetone, ethyl acetate, and thiourea.
► Simplified Pitzer model applied successfully to correlate these data.
► Linear temperature dependence of the mixing Pitzer parameter was observed.