Improving performance of liquid-liquid extraction with temperature for mass transfer resistance in both phases

The influence of temperature on hydrodynamic and mass transfer of liquid-liquid extraction process was investigated with single drop experiments in a jacketed pilot column and with respect to variations in physical properties. The applied temperatures were within the conventional range of 15-40 degrees C. In order to include the influence of mass transfer direction, the chemical system of 4-methylpentan-2-oneacetic acid-water was chosen which exhibits mass transfer resistance against solute transfer in its both phases. Results revealed the significant impact of temperature on the rate of mass transfer with an average enhancement of 46.1% and 36.1% for dispersed to continuous phase and vice versa directions, respectively. The extraction efficiency is the most effective term in this regard, due to enhancement of solute diffusivity in phases. The data were nicely reproduced using a correlation of dimensionless numbers to obtain the effective diffusivity for substitution instead of molecular diffusivity in Newman's equation. The model predicts the overall mass transfer coefficient at different temperatures. (c) 2013 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.