| 摘要 |
PURPOSE:To prepare an anhydrous lower alcohol efficiently at low cost, by treating a dilute aqueous solution of lower alcohol in order of extraction, extractin and separation, and azeotropic distillation, concentrating the extraction residue. CONSTITUTION:A dilute aqueous solution of lower alcohol is optionally sterilized and treated by the device 1 for removing suspended matters, introduced to the extractor 2, brought into contact with an organic solvent such as an organic acid, alcohol, etc., extracted, separated into an extracted solution and the extraction residue by the separator 3, the extraction residue is introduced to the alcohol concentration device 4, concentrated to 10-80wt% alcohol concentration, returned to the extractor 2. While water of the extracted solution is optionally reduced, the solution is sent to the azeotropic separator 5, separated by an azeotropic composition consisting of a low-boiling solvent, water and a lower alcohol with the low-boiling solvent in the extraction solvent, it is returned to the extractor 2, the azeotropic residue is separated into an anhydrous lower alcohol and the remaining solvent, and the remaining solvent is returned to the extractor 2. |
