Investigating thermodynamic properties of LiCl in amide–water mixtures with ɛ-increasing and ɛ-decreasing solvent at 298.15 K

•Thermodynamics of LiCl + amides (urea, NMF, DMF, DMA) + water system were reported.•The Pitzer, modified Pitzer and extended Debye–Hückel models were used.•The mean activity coefficients, excess Gibbs free energy were calculated.•The standard solubility product and the primary hydration number were obtained.

This article deals with the mean activity coefficients of LiCl in amide–water mixtures with both ɛ-increasing co-solvent (urea–water, N-methylformamide–water), and ɛ-decreasing co-solvent (N,N-dimethylformamide–water, N,N-dimethylacetamide–water) systems at 298.15 K by potentiometric method. Meanwhile, thermodynamic properties including the osmotic coefficients, the excess Gibbs free energy, the standard solubility product, the primary LiCl hydration number and the standard free energy of transference from water to the mixtures were also calculated. The nonideal behavior of these systems has been discussed in terms of the Pitzer, the Modified Pitzer and the extended Debye–Hückel equations parameters.

Graphical abstractThe thermodynamic properties of LiCl in amide–water mixtures with both ɛ-increasing co-solvent (urea–water, N-methylformamide–water), and ɛ-decreasing co-solvent (N,N-dimethylformamide–water, N,N-dimethylacetamide–water) systems at 298.15 K were determined by potentiometric method.Figure optionsDownload full-size imageDownload as PowerPoint slide