서강대학교

초록/요약

Liquid-liquid equilibria were measured for water + 2,3-butanediol + 2-methyl-1-pentanol at 298.15, 308.15 and 318.15 K under atmospheric pressure. The separation factors and distribution coefficient were evaluated from the liquid−liquid equilibrium data for each ternary mixture. The consistency of the tie-line results was ascertained using an Othmer-Tobias plot and Hand plot. The nonrandom two-liquid (NRTL) and universal quasi-chemical activity coefficient (UNIQUAC) models were used to correlate the experimental LLE data. The binary interaction parameters and RMSD calculated from the NRTL and UNIQUAC models were also reported. Both models successfully predicted the experimental tie-line data, with the average root-mean-square deviations (RMSD) less than 1.58 % for water + 2,3-butanediol + 2-methyl-1-pentanol. Isobaric VLE data for binary systems of water + 2,3-butanediol were studied at 101.3, 80, 66.7, 50 and 40 kPa. A circulation-type equilibrium apparatus with on-line gas chromatography analysis was used for this work. The experimental data were correlated with the NRTL and UNIQUAC model. The overall average relative deviations of Temperature (ARD-T (%)) and vapor phase compositions (ARD-y (%)) between experimental and calculated values were 0.708 and 1.264 % using NRTL and 0.753 and 1.124 using UNIQUAC, respectively. From these results, we concluded that the NRTL and UNIQUAC model provides good description for predicting phase equilibrium behavior of this binary system.