US Patent 7378549 Process for the reactive extractive extraction of levulinic acid

A process for the reactive extraction of levulinic acid from an aqueous mixture having levulinic acid, wherein the aqueous mixture is contacted with a liquid esterifying alcohol, the alcohol having at least four carbon atoms and is substantially water-immiscible, at esterification conditions in the presence of a catalyst to form a levulinate ester, wherein the amount of the alcohol is such that the alcohol extracts the levulinate ester from the aqueous mixture. Further, an aqueous phase, having the catalyst and a reduced levulinic acid content, and an organic phase, having the alcohol and the levulinate ester, are formed.