Ethanol Recovery from Low-Concentration Aqueous Solutions Using Membrane Contactors with Ionic Liquids

Recovery of alcohols from diluted aqueous solutions is highly energy-intensive. In order to reduce the costs of concentration of alcohols, membrane processes (including membrane extraction) are used. This paper reports the results of ethanol concentration from diluted aqueous solutions using a hollow fiber membrane contactor with ionic liquid. The studies were performed using a contactor with microporous hollow fiber membranes. The membrane creates a barrier between the feed and extracting solvent, also providing a large mass transfer area. In the process, selected ionic liquid presenting different selectivity towards ethanol was used as extractant. The experiments were performed with feed concentrations of ethanol ranging from 1 to 5 wt.% and various feed flow rates ranging from 1 to 8 dm³/h.