The extraction of acetic acid by liquid membrane process

Liquid membranes have potential of several advantages, some of which are of particular interest for the recovery of carboxylic acid and amino acids: selectivities higher than those attainable by current seperation methods, saving on energy cost for final concentration of seperated products, high massfluxes, and low capital and operation costs.The extraction of acetic acid from aqueous solutions by emulsion type liquid membrane process has been experimantally investigated using 2?10% (w/v) acetic acid solution, 3?8% Alamine 300 as carrier, 3?6% Span 80 as surfactant, and 5?20% Na2CO3 as stripping solutions.Such important parameters as mixing speed, surfactant concentration, solvent type, the carrier type (Alamine 300, Alamine 336, TBP) and concentration, stripping agent Na2CO3 concentration, feed solution pH and concentration, and affecting the rate of extraction and efficiency, have been experimentally examined.Acetic acid has been successfully extracted and concentrated from aqueous solutions using the emulsion liquid membrane process. About 86% extraction of acetic acid in the solution has been achieved in about 10 minutes in a stirred vessel.Key Words: Liquid membrane, emulsion liquid membrane, supported liquid membrane, extractant, Alamine 300, Alamine 336, surfactant, acetic acid extraction