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:
Apr. 06, 2010
Filed:
Dec. 09, 2005
Syed Mohammed Azhar Hashmi, Riyadh, SA;
Sulaiman Al-luhaidan, Riyadh, SA;
Syed Mohammed Azhar Hashmi, Riyadh, SA;
Sulaiman Al-Luhaidan, Riyadh, SA;
Saudi Basic Industries Corporation, Riyadh, SA;
Abstract
The present invention relates to a process for preparing purified terephthalic acid [PTA,], comprising the steps: dissolving crude terephthalic acid [CTA] in an aqueous medium in a reactor; hydrogenating CTA at a temperature of about 260-320° C. and a pressure of about 1100-1300 psig using a hydrogenation catalyst; crystallizing terephthalic acid in the reactor by lowering the temperature of the solution to about 160° C. without evaporation cooling; transferring the content of the reactor to a filtration unit; filtrating the content at a temperature of about 140-160° C. and a pressure of about 40-100 psig, preferably 80-100 psig to obtain a filter cake, washing the filter cake obtained with water having a temperature of about 140-160° C. in the filtration unit; and drying the filter cake.