Title:
高純度テレフタル酸の製造方法
Document Type and Number:
Japanese Patent JP3979505
Kind Code:
B2
Abstract:
There is disclosed a process for producing highly pure terephthalic acid by converting a slurry of terephthalic acid crystals in acetic acid solvent which crystals are obtained by liquid-phase oxidation of p-alkylbenzene, into a slurry thereof in water solvent by mother liquor replacement and then subjecting the latter slurry to a catalytic hydrogenation treatment which process comprises the steps of introducing the slurry of terephthalic acid crystals in acetic acid into a mother liquor replacement column at the top portion; forming an accumulation layer of the terephthalic acid crystals at the bottom portion by the sedimentation of the crystals; feeding replacing water sufficient for the formation of upward rising stream of water to the inside of the column at the bottom portion; and withdrawing the accumulation layer of the crystals from the bottom portion of the column. The accumulation layer is kept at a slightly fluidized stable state and is smoothly withdrawn from the bottom of the column by slowly rotating an arm-type agitation blade placed in the layer or by feeding the replacing water dividedly into two trains.
Inventors:
Fumio Ogoshi
Masato Inari
Fumiya Aima
Masato Inari
Fumiya Aima
Application Number:
JP11829995A
Publication Date:
September 19, 2007
Filing Date:
May 17, 1995
Export Citation:
Assignee:
Mitsubishi Gas Chemical Co., Ltd.
TOYO BOSEKI KABUSHIKI KAISHA
Mizushima Aroma Co., Ltd.
TOYO BOSEKI KABUSHIKI KAISHA
Mizushima Aroma Co., Ltd.
International Classes:
C07C51/487; C07C63/26; C07C51/43
Domestic Patent References:
| JP1160942A | ||||
| JP33005410B1 |