Investigation of Packing Effect on Mass Transfer Coefficient in a Single Drop Liquid Extraction Column

Mass transfer coefficients of rising drops in spray and packed columns with random and structured packing in a liquid-liquid extraction operation were experimentally measured and the results compared. In this work, a high interfacial tension chemical system of toluene-acetic acid-water in a structured packed column is investigated. Results of random and structured packing show that random types are effective only for a drop size less than 9 mm, while the structured ones are shown to have a positive effect on mass transfer coefficient in a wide drop size range. Furthermore, structured packing proved to be slightly more effective than random packing in improving the mass transfer coefficient. The effect of drop size on mass transfer coefficient has also been studied in this work and the results showed that when the drop diameter increases, the mass transfer coefficient increases too. Finally, new correlations for the prediction of the mass transfer coefficient in both a random and structured packed column have been introduced which are in better agreement with the experimental data in comparison with those resulted from Newman, Kronig-Brink and Handlos-Baron models.