Emulsion liquid membrane pertraction of imidazole from dilute aqueous solutions by Aliquat-336 mobile carrier Original Research Article

This paper reports a study of batch extraction of imidazole from dilute aqueous solutions using an emulsion liquid membrane (ELM) technique. Capabilities of this method in the separation of solute from dilute aqueous solutions are shown. Studies on the extraction equilibrium between organic and aqueous phases were performed. Effects of various parameters such as agitation time, speed of emulsification, internal phase concentration, extractant concentration (carrier), volume ratio of organic phase to aqueous internal phase and concentration of surfactant on the membrane stability as well as contact time, stirring speed, feed concentration, pH of external phase and volume ratio of the emulsion phase to the aqueous external phase on pertraction performance were studied. The organic phase consists of kerosene and n-heptane as diluent, Aliquat-336 as extractant and sorbiton monooleate (Span-80) as surfactant. HCl solution is used as the internal stripping phase. The results showed that by appropriate selection of the extraction and stability conditions, the maximum recovery of imidazole from the feed were achieved within a few minutes. The influence of the HCl concentration on stripping efficiency was investigated.