Determination and intermolecular interaction analysis of the liquid–liquid equilibrium of water, acrylic acid, and different solvents at 303.2 K and 101.3 kPa

Abstract

To explore the effective treatment of acrylic acid wastewater, liquid–liquid equilibrium (LLE) data for water + acrylic acid + {n-propyl acetate, n-butyl acetate, n-heptanol, and methyl isopropyl ketone} at 303.2 K and 101.3 kPa were measured respectively. The distribution coefficients (D) and separation factors (S) were used to assess the extraction effectiveness of the four solvents, and the results of the comparative data showed that the D values of the four solvents for acrylic acid ranged from 1.6 to 4.4, and the S values were in the order of n-butyl acetate > n-propyl acetate > MIPK > n-heptanol. The experimental data were fitted by NRTL and UNIQUAC models to obtain the binary interaction parameters, and the obtained above parameters were proved reliable by the mixing surface analysis method of Gibbs energy topology. The root mean square deviation (RMSD) of both models did not exceed 0.0051 and 0.0077, respectively. In addition, σ-profiles analyzed the differences in extraction effects in terms of interactions and interaction energies, and the analyses showed that the theoretical calculations are in agreement with the experimental results.