Study on the Effect of Alkane Chain Length on the Extraction of Ethyl Acrylate from Aqueous Solution and Correlation of Thermodynamic Model

To explore the performance of n-alkanes with different alkyl chain lengths to extract ethyl acrylate from aqueous solutions, LLE data for the ternary system [water + ethyl acrylate + n-alkanes (C5, C6, C7, and C12)] were measured at 303.2 K, 101.25 kPa. Partition coefficients and separation factors were calculated as parameters for the evaluation of extractant extraction performance, where n-dodecane had the highest S and D values, indicating that it is a suitable extractant. The NRTL and UNIQUAC models were used to correlate the systems involved in this work, and the optimal binary interaction parameters were obtained. The smaller rmsd values indicate the good applicability of these two models for this ternary system, with values less than 0.88 and 0.78%, respectively. The mixed surface analysis of the Gibbs energy topology was used to test the obtained parameters, and the results showed that the parameters were reliable. In addition, the molecular force between the extractant and ethyl acrylate was determined to be van der Waals force by σ-Profile analysis and increased with the number of carbon atoms of n-alkanes.