Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acids and salts thereof
Reexamination Certificate
2007-08-28
2007-08-28
Page, Thurman K. (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acids and salts thereof
C422S031000, C570S101000
Reexamination Certificate
active
10574273
ABSTRACT:
A method for producing high purity terephthalic acid wherein a slurry having an acetic acid solvent and, dispersed therein, crude terephthalic acid crystals which has been prepared by subjecting a p-alkyl benzene to a liquid phase oxidation in a solvent of acetic acid is continuously converted to a water slurry by the mother liquid exchange, and then the resultant water slurry is subjected to a hydrogenation treatment, which comprises introducing the above acetic acid slurry to a tower having a center axis having a plurality of agitating blades at the top thereof, to form a region having a high concentration of terephthalic acid crystals in the tower through the sedimentation of the terephthalic acid crystals, supplying the water for substitution to the bottom of the tower in such a manner to form an upward water flow while generating a revolving flow of the high concentration region by the rotation of the agitation blade, to thereby subject said terephthalic acid crystals and said upward water flow to a counter-flow contact, and taking out the acetic acid from a portion being upper than the supply port for the acetic acid slurry while withdrawing the terephthalic acid crystals having contacted with the upward water flow together with the water for substitution from the tower bottom. The above method allows the substitution of the acetic acid solvent of the acetic acid slurry with water, with a high substitution percentage.
REFERENCES:
patent: 5008450 (1991-04-01), Yamamoto et al.
patent: 5712412 (1998-01-01), Inary et al.
patent: 5777161 (1998-07-01), Inary
patent: 01-160942 (1989-06-01), None
patent: 08-231465 (1996-09-01), None
patent: 09-286758 (1997-11-01), None
patent: 09-286759 (1997-11-01), None
patent: 10-45667 (1998-02-01), None
patent: 2000-191583 (2000-07-01), None
Fujita Hideaki
Machida Hiroshi
Namiki Nobuo
Waguri Yoshio
Antonelli, Terry Stout & Kraus, LLP.
Lao MLouisa
Mitsubishi Gas Chemical Company Inc.
Mizushima Aroma Company, Ltd.
Page Thurman K.
LandOfFree
Method for producing high purity terephthalic acid does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for producing high purity terephthalic acid, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for producing high purity terephthalic acid will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3885840