Removal of aniline from aqueous solution in a mixed flow reactor using emulsion liquid membrane

The emulsion liquid membrane (ELM) technique was employed in a mixed flow reactor (MFR) for the removal of aniline from dilute aqueous solution. The extent of removal of aniline was experimentally determined under various operating conditions such as, feed to emulsion ratio (F:E), internal reagent concentration (C-h), stirrer speed (n), residence time in the reactor (tau), and feed concentration (C-0). The mass transfer within the emulsion globule was modeled by incorporating the diffusion of solute within the reacted (spent) emulsion phase, and allowing for the gradual shrinkage of the unreacted zone of the internal reagent. The reaction between the solute and internal reagent at the moving boundary (interface) of the reacted and unreacted zones was assumed to be first order reversible. The removal of aniline was found to increase with increase in tau, C-h and n, and with decrease in the F:E ratio and C-0. The maximum removal of aniline obtained in this study was 98.53%. The data and the model results were found to be in good agreement in most cases. The discrepancy between the model results and the data observed at higher n and tau were attributed due to the rupture of emulsion globules and non-ideal flow conditions existing within the reactor, respectively. (C) 2003 Elsevier B.V. All rights reserved.