Thermodynamic properties of (LiCl + N,N-dimethylacetamide) and (LiBr + N,N-dimethylacetamide) at temperatures from (323.15 to 423.15) K

Abstract

Precise vapor pressure data for LiCl and LiBr solns. in N,N-dimethylacetamide are given for T = 323.15 to 423.15 K. The molality ranges covered in this study are about m = 0.073 to 1.89 mol·kg-1 for lithium chloride and m = 0.06 to 1.75 mol·kg-1 for lithium bromide. Osmotic coeffs. are calcd. by taking into account the second virial coeff. of N,N-dimethylacetamide. The parameters of the extended Pitzer-ion interaction model of Archer, of the MSA-NRTL model, and of the chem. model of Barthel are evaluated. These models accurately reproduce the exptl. osmotic coeffs. within different concn. ranges. The parameters of the Pitzer-ion interaction model of Archer are used to calc. the mean molal activity coeffs. and excess Gibbs free energies. The non-ideal behaviors of these systems are discussed in terms of the model parameters.