Extractive distillation ethanol/isopropanol/water process

Figure 13.24. Composition profiles and flowsketches of two extractive distillation processes, (a) Separation of methylcyclohexane and toluene with phenol as solvent (data calculated by Smith, 1963). (b) Separation of aqueous ethanol and isopropanol, recovering 98% of the ethanol containing 0.2 mol % isopropanol, employing water as the solvent. Flow rates are in mols/hr (data calculated by Robinson and Gilliland, 1950).

Some AvaUahle Data. A brief list of extractive distillation processes of actual or potential commerical value is in Table 13.7 the column of remarks explains why this mode of separation is adopted. The leading applications are to the separation of closeboiling aromatic, naphthenic, and aliphatic hydrocarbons and of olefins from diolefins such as butadiene and isoprene. Miscellaneous separations include propane from propylene with acrylonitrile as solvent (DuPont, U.S. Pat. 2,980,727) and ethanol from isopropanol with water as solvent [Figure 13.23 (b)]. 

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