Catalytic purification of dicarboxylic aromatic acid

Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acids and salts thereof

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

562485, 562412, C07C 5142

Patent

active

056167920

ABSTRACT:
Processes using a titanium dioxide-supported purification catalyst are disclosed for purification of relatively impure dicarboxylic aromatic acid produced by liquid-phase oxidation of a suitable benzene or naphthalene having two oxidizable ring substituents, and/or by recovery from polyester resin comprising repeating units of the dicarboxylic aromatic acid residue and repeating units of dihydric alcohol residue. Purification comprises passing an aqueous solution of dicarboxylic aromatic acid with small amounts of organic impurities consisting of oxygen-containing aromatic co-products of oxidation and/or other organic components, through a particulate bed of purification catalyst comprising a noble metal on a titanium dioxide support under conditions suitable for decarbonylation of organic impurities. Generally, at least one weight percent of the titanium dioxide support is in the ruffle crystalline phase. Optionally, effluent aqueous solution from the bed containing noble metal on the titanium dioxide support is passed through a subsequent particulate bed of another purification catalyst in the presence of a molecular hydrogen-containing gas. Hydrogenation of the aqueous solution subsequent to decarbonylation further reduces organic impurities in dicarboxylic aromatic acid recovered by crystallization and separation from the aqueous solution.

REFERENCES:
patent: 3584039 (1971-06-01), Meyer
patent: 3726915 (1973-04-01), Pohlmann
patent: 4201872 (1980-05-01), Kimura et al.
patent: 4317923 (1982-03-01), Imai
patent: 4394299 (1983-07-01), Puskas et al.
patent: 4405809 (1983-09-01), Stech et al.
patent: 4467110 (1984-08-01), Puskas et al.
patent: 4629715 (1986-12-01), Schroeder
patent: 4652674 (1987-03-01), James et al.
patent: 4743577 (1988-05-01), Schroeder et al.
patent: 4831008 (1989-05-01), Timmer et al.
patent: 4892972 (1990-01-01), Schroeder et al.
patent: 5292934 (1994-03-01), Sikkenga et al.
patent: 5362908 (1994-11-01), Schroeder et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Catalytic purification of dicarboxylic aromatic 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 Catalytic purification of dicarboxylic aromatic acid, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Catalytic purification of dicarboxylic aromatic acid will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-540655

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.