서강대학교

초록/요약

In this work, liquid-liquid equilibrium (LLE) data has been measured for the water + 2,3-butanediol + 2-methyl-2-butanol ternary system and at water + 2, 3-butanediol + 3-methyl-3-pentanol system at 298.2, 308.2, and 318.2 K under atmospheric pressure. Binodal solubility curves and complete ternary phase diagrams were experimentally obtained in mass fraction at these three different temperatures about each system respectively. To verify the consistency of tie-line data, Othmer-Tobias and Hand plots method were used. The universal quasi-chemical activity coefficient (UNIQUAC) and non-random two-liquid (NRTL) activity coefficient models were used to correlate the experimental tie-line data. Binary interaction parameters calculated from these models have also been reported. The average root-mean-square deviations (RMSD) were calculated about both systems. The average RMSD value is less than 1.5%. Both models successfully predict the calculated data about each system. Distribution coefficients and separation factors about each solvent (2-methyl-2-butanol and 3-methyl-3-pentanol) were calculated to evaluate the solvent efficiency for each tie-line data. As a result, the each solvent are good extraction solvents. Also isobaric vapor-liquid equilibrium experiment about two systems (2-methyl-2-butanol + 2,3-butanediol and 3-methyl-3-pentanol + 2,3-butanediol) were conducted at 101.3, 81, 60.8 and 40.5 kPa. Experimental data were correlated using the activity coefficient model such as NRTL and UNIQUAC. To evaluate the data, several tests were carried out. RMSE value was used to confirm the data soundness and Van-less method was used to evaluate the data accuracy. The ARD was calculated to numerically estimate the error between experimental data and correlated data. Also, data consistency was evaluated using the ARD value. The RMSE % is less than 5% and Van-less test value is about 1 all over the experiment data. The average relative deviations of the Temperature (ARD-T (%)) is not over 0.5 % and the average relative deviations of the vapor-phase composition (ARD-y (%)) is less than 3%. Depending on the results, NRTL and UNIQUAC models provide a good explanation for predicting the equilibrium behavior of this system.