Removal of copper and zinc from aqueous solutions and industrial effluents using emulsion liquid membrane technique

Abstract

AbstractCopper and zinc were removed from dilute aqueous solutions together with recovery of copper from electroplating wastewater containing copper ions by emulsion liquid membrane (ELM) technique. The effects of surfactant concentration, carrier concentration, emulsification speed, emulsification time, internal phase stripping agent concentration, and aqueous‐to‐organic phase (A/O) volume ratio on the emulsion stability and breakup have been studied in detail and reported. A mixture of kerosene as diluent, span 80 as surfactant, di‐(2‐ethylhexyl) phosphate as carrier was used. An experimental study was performed to optimize the pH of the aqueous external phase based on distribution coefficient of solute between aqueous external phase and organic (membrane) phase. The batch extraction was carried out under various experimental conditions such as agitation time, agitation speed, membrane‐to‐external phase (M/E) ratio, solute concentration in the feed phase and carrier concentration in membrane phase on the percentage recovery of zinc and copper ions in their respective feed streams and the operating parameters have been optimized for maximum recovery. It was found that 84% of copper and 86% of zinc were removed from aqueous solution with a concentration factor of 5. It was also found that ELM extraction of copper from wastewater was around 8–17% less than that of the synthetic solution. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.