| 摘要 |
PURPOSE:In the concentration of ethanol in aqueous ethanol solution, 1,1- difluoroethane is used as a selective extraction solvent for ethanol to enable advantageous concentration of ethanol with the energy consumption saved for concentration. CONSTITUTION:An ethanol-containing aqueous solution, which may contain sludge, is brought into contact with liquid 1,1-difluorethane as an extractive solvent to effect the extraction of ethanol, at the same time, when the aqueous solution contains sludge, the sludge is precipitated and removed out of the system. Then, the extractive solvent is removed from the extract phase 4, 5, when needed, the ethanol collected 6 is distilled to remove water therefrom without scaling trouble even when sludge is contained in the aqueous solution to give concentrated ethanol with energy consumption saved, at low costs. The extractive solvent is low in toxicity and high in ethanol distribution coefficient. |
