Membrane contactor for efficient alcohol recovery
Biobased feedstocks are displacing oil and gas for fuels, chemicals, and fibers.  This displacement requires energy-efficient conversion and recovery processes.  As product titer decreases, the energy required for product recovery increases.  Previously, we presented the Separative Bioreactor, a membrane technology to recover organic acids and other charged products from fermentation broths.  Here we present a membrane-contactor based technology to recover alcohols and other neutral species from fermentation broths.  The membrane contactor uses functionalized membranes and ionic liquid extraction solvents to drive the separation.  The process exhibits higher separation factors than observed for either the membrane or solvent separately.  To date, technology has been applied to ethanol and butanol.  If we are able to scale it up, the membrane contactor/ionic liquid technology will significant decrease the energy required to recover butanol from fermentation broths.  The technology could also improve the energy efficiency for cellulosic ethanol recovery at titers exhibited in syngas fermentation. The following file types may be uploaded: .