NOVELTY - Preparing butanol from fermentation broth in a fermentor (2), comprises: providing liquid fermentation broth comprising carbohydrate substrate, nutrients and water in which alcohol is produced by the growth of Saccharomyces or recombinant Saccharomyces; contacting ionic liquid with fermentation broth or its portion, to form ionic liquid phase and aqueous phase where the butanol or its portion is more soluble in ionic liquid phase than aqueous phase; and separating butanol-rich ionic liquid phase from aqueous phase and optionally recovering butanol from ionic liquid phase.    USE - The process is useful for preparing butanol, which is useful in motor fuel (all claimed). The process is useful for recovering ethanol, 1-butanol, 2-butanol, isobutanol (2-methyl-1-propanol) or tertiary butanol (2-methyl-2-propanol) from fermentation broth, where recovered alcohols are used in industrial commodity chemical applications, as fuels or fuel additives, and for blending with fossil fuels (gasoline).    ADVANTAGE - The process provides: high alcohol productivity within a very short fermentation time; butanol which is favored as a fuel or fuel additive, since it yields only carbon dioxide and little or no sulfur oxide or nitrogen oxides when burned in the standard internal combustion engine, and it causes a limited amount of corrosion. The process utilizes microorganisms which provide high selectivity, low accumulation of byproducts, high alcohol yield, high fermentation rate, good tolerance towards both increased alcohol and substrate concentrations, good tolerance toward the extracting solvent and good tolerance toward lower pH values.    DETAILED DESCRIPTION - Preparing butanol from fermentation broth in a fermentor (2), comprises: providing a liquid fermentation broth comprising carbohydrate substrate, nutrients and water in which an alcohol is produced by the growth of Saccharomyces or a recombinant Saccharomyces; contacting at least one ionic liquid with the fermentation broth or its portion, to form from the resulting mixture an ionic liquid phase and an aqueous phase where the butanol or its portion, is more soluble in the ionic liquid phase than the aqueous phase; and separating the butanol-rich ionic liquid phase from the aqueous phase and optionally recovering the butanol from the ionic liquid phase, where the ionic liquid is comprised of a cation comprising pyrrolidin-2-one or imidazolium, and an anion comprising levulinate, bis(trifluoromethane)sulfonamide or hexafluoropropane sulfonate.    DESCRIPTION OF DRAWING(S) - The figure shows an apparatus for recovering ethanol from fermentation broth.    Fermentor (2)    Stream (4, 8, 14, 16, 20, 22)    In-situ product removal module (6)    Product recovery module (10)    Purge/make-up streams (24)