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:
Oct. 12, 1982
Filed:
Jan. 21, 1981
Jesse G Wendle, Jr, New Hanover County, NC (US);
Hercofina, Wilmington, NC (US);
Abstract
Disclosed is an improvement in a method for the recovery for recycle to the cooxidation-coesterification process for the production of dimethyl terephthalate from p-xylene, air and methanol of oxidation catalyst by aqueous extraction of a distillation residue containing the same. To minimize recycle of any iron present in the residue, iron oxidant material (for example, hydrogen peroxide) is admixed in one embodiment with the residue and water in the aqueous extraction procedure, and in a second embodiment with the resulting aqueous extract. In both embodiments, if any iron is present, it is precipitated. In the first embodiment the precipitate stays with the residue. In the second embodiment the aqueous extract is separated from the precipitate.