Thermodynamic studies on CsF/RbF in N,N-dimethylformamide/N,N-dimethylacetamide + H2O mixtures at T = 298.15 K

• Thermodynamic properties of CsF/RbF + DMF/DMA + H2O ternary systems were determined.
• The Pitzer and extended Debye–Hückel equations were utilized.
• Mean activity coefficients and standard Gibbs free energy of transfer were calculated.

This article investigated the thermodynamic properties in a ternary system (CsF/RbF + DMF/DMA + H2O) at T = 298.15 K using potentiometric methods. The experimental data were correlated using the Pitzer and extended Debye–Hückel equations. The mean activity coefficients, excess Gibbs free energy and the standard Gibbs free energy of transfer, together with the parameters of above thermodynamic models, were determined.

The thermodynamic properties of CsF or RbF in N,N-dimethylformamide + H2O or N,N-dimethylacetamide + H2O mixtures at T = 298.15 K were reported herein. The values of mean activity coefficients decrease with the increasing of the concentration of CsF, and with the increasing of difference mass fraction of DMF in the mixtures. (■, w = 0.00; , w = 0.10; ▴, w = 0.20; ◊, w = 0.30).Figure optionsDownload as PowerPoint slide