Energy Efficient Separation of Ethanol From Aqueous Solution

The present invention provides methods and systems for extracting ethanol from an ethanol-water solution comprising (1) extracting ethanol from an ethanol-water solution with a first solvent comprising an esterified fatty acid, wherein the esterified fatty acid comprises a hydroxylated fatty acid component and an alcohol component such that the alcohol component is a C3-6 alcohol, such that the distribution coefficient for ethanol in the mixture of the ethanol-water solution and the first solvent is at least 0.02 favoring the transfer of ethanol from the ethanol-water solution to the first solvent, thereby extracting the ethanol from the ethanol-water solution into the first solvent, and (2) extracting the ethanol-enriched first solvent with carbon dioxide, such that the carbon dioxide is at a liquid or near supercritical phase, wherein the distribution coefficient for ethanol in a mixture of the first solvent and the carbon dioxide is at least 0.1 favoring the transfer of ethanol from the first solvent to the carbon dioxide.