Extraction and pertraction of phenol through bulk liquid membranes

Abstract

AbstractThe extraction and pertraction of phenol through a bulk liquid membrane (BLM) with Cyanex® 923, Amberlite® LA‐2 and trioctylamine (TOA) as carriers were studied. Cyanex® 923 was selected as the best carrier for pertraction. The distribution coefficient of phenol for solvents with carrier and pure n‐alkanes, the individual mass‐transfer coefficient at the extraction interface and the initial flux of phenol through the extraction interface (JFo) decreased in the order: Cyanex® 923 > Amberlite® LA‐2 > TOA ≫ pure n‐alkanes. The opposite order was observed for the value of the mass‐transfer coefficient in BLM and the maximum flux of phenol through the stripping interface (JRmax). At constant driving forces the maximum fluxes through the extraction and stripping interfaces were similar when amine carriers were used. However, JRmax was lower than JFo for Cyanex® 923. Although the kinetics of stripping was the rate‐determining step, the flux of phenol was significantly higher than in pertraction with amine carriers. The adsorption of the carrier at aqueous phase/membrane interfaces was probably responsible for the rapid and slow transfer of phenol through the extraction and stripping interface, respectively. Copyright © 2004 Society of Chemical Industry