Liquid-Liquid Extraction in a Microextractor: A Laboratory Examination and Thermodynamic Modeling of N-Hexane + Benzene + Sulfolane System

Abstract

This study aimed at investigating liquid-liquid extraction of the three-component n-hexane + benzene + sulfolane system in a micro extractor. Experiments were carried out in a microtube with a diameter of 800μm using a T-shaped micromixer at a residence time of 15s. Temperature and the ratio of solvent (sulfolane) to feed (95% n-hexane + 5% benzene) investigated as operational variables. The temperature was investigated at (313.15, 323.15, and 333.15) K, and the solvent to feed ratio was investigated in five states including (0.33, 0.50, 1.00, 2.00, and 3.00) mL/mL. The results of experimental design and statistical analysis showed that operational variables had a significant impact on the distribution coefficient and selectivity. It was found that distribution coefficient and selectivity reached their highest levels at (313.15 and 32315) K, respectively. In addition, in the low volumetric solvent to feed ratio (0.33ml/ml), the highest levels of distribution coefficient and selectivity were been obtained. Finally, the results obtained for liquid-liquid extraction of n-hexane + benzene + sulfolane were assessed using NRTL and UNIQUAC models, and the results confirmed the high accuracy of both models.

Keywords

• liquid-liquid extraction
• microtube
• optimization
• thermodynamic modeling
• nrtl
• uniquac