Experimental and Modeling Study for the Salting-Out Extraction of Acetic Acid from Aqueous Solutions with Kerosene

Abstract

The outstanding salting-out effect on the liquid–liquid equilibrium of water + acetic acid + kerosene was studied at a temperature of T = 298.2 K and under the ambient pressure of p = 81.5 kPa. The importance of this study relates to the kerosene availability around the world and that water sources are salty in most cases. The results revealed that the recovery of acetic acid from aqueous solutions was considerably boosted with 0.005 and 0.010 mass fractions of NaCl, Na2SO4, and MgSO4. The separation factors with the maximum enhancements of 81.62, 158.43, and 287.74%, respectively, were achieved with the salts under the used higher concentration. Consistent with the Hofmeister series, the salting-out effect appeared in the order of MgSO4 > Na2SO4 > NaCl. Meanwhile, the validity of the experimental data was confirmed based on the Eisen–Joffe equation. By considering a surrogate mixture for kerosene, composed of 80 wt % n-decane and 20 wt % 1,2,4-trimethylbenzene, the thermodynamic models of NRTL and UNIQUAC were used to correlate the data. Excellent agreements between the experimental and predicted values were found with very low maximum root mean square deviations of 0.0062 and 0.0068 for the models, respectively.