| 摘要 |
PURPOSE:To remarkably reduce the allyl alcohol concentration is a circulating solution and carry out purification at a low equipment and operating cost, by carrying out recovery of the allyl alcohol from a hydrolysis product of allyl acetate with distillation columns and extraction column in combination. CONSTITUTION:Allyl acetate (AAc) is hydrolyzed in a reaction column 2 to feed a low-boiling fraction (21a) consisting of allyl alcohol (AAL), AAc and water from the top of the first distillation column 21 to a decanter 22 where the low-boiling fraction (21a) is separated into an oily layer (22a) containing much AAc and an aqueous layer (22b) containing little AAc. The oily layer (22a) is then fed to an extraction column 23 and the aqueous layer (22b), together with a bottom liquid (23b) of the extraction column 23, is introduced into the second distillation column 24. A low-boiling fraction (24a) containing AAL, water and a small amount of AAc is then fed to the extraction column 23 where the AAL is extracted with water as a solvent to circulate an overhead liquid (23a) containing no AAL. A high-boiling fraction (24b) consisting of the AAL and water is fed to the third distillation column 25 to recover the concentrated AAL and circulate the water from the bottom of the column 25 to the extraction column 23.
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