Title:
METHOD FOR SEPARATING ACETAL
Document Type and Number:
Japanese Patent JP3166295
Kind Code:
B2
Abstract:
PURPOSE: To obtain a method for efficiently separating an acetal in separating a mixture, composed of a dimethyl acetal and methanol and having the composition close to the azeotropic one by distillation.
CONSTITUTION: (1) A mixture solution consisting essentially of methanol and acetaldehyde dimethyl acetal is distilled and separated in a distillation column. In the process, n-pentane or cyclopentane is used as an azeotropic solvent to separate a small amount of the dimethyl acetal as an azeotropic mixture of methanol-n-pentane-dimethyl acetal or an azeotropic mixture of methanol- cyclopentane-dimethyl acetal from the top of the distillation column. Thereby, a fraction consisting essentially of the dimethyl acetal is distilled away from the bottom of the column. (2) The resultant mixture consisting essentially of the distilled away n-pentane, methanol and dimethyl acetal or cyclopentane, methanol and dimethyl acetal is separated. In the process, the n-pentane or cyclopentane is separated by countercurrent extraction with water. (3) The n-pentane or cyclopentane separated by the extraction is reused as the azeotropic solvent.
Inventors:
Toshiyuki Aizawa
Kunitoshi Wakabayashi
Hitoshi Nakamura
Kunitoshi Wakabayashi
Hitoshi Nakamura
Application Number:
JP12639592A
Publication Date:
May 14, 2001
Filing Date:
May 19, 1992
Export Citation:
Assignee:
SHOWA DENKO K.K.
International Classes:
C07C41/58; C07C43/303; (IPC1-7): C07C43/303; C07C41/58
Domestic Patent References:
| JP5832838A | ||||
| JP356134A | ||||
| JP5836425A | ||||
| JP6229419B2 |
Attorney, Agent or Firm:
Taira Yaguchi