The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 18, 2002
Filed:
Jan. 14, 2000
Applicant:
Inventors:
David Parker, Middlesbrough, GB;
Fiona Mary Campbell, Cleveland, GB;
Andrew Harrison, Stokesley, GB;
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 5/142 ;
U.S. Cl.
CPC ...
C07C 5/142 ;
Abstract
A method for recovering and recycling excess hydrogen from process vent streams in the production of highly pure terephthalic acid where the production of the pure terephthalic acid comprises catalytically hydrogenating impure terephthalic acid, which typically contains 4-carboxybenzaldehyde (4-CBA), color bodies and other impurities, in aqueous liquid phase solution at elevated temperature and pressure.