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:
Nov. 18, 2025
Filed:
Jun. 09, 2022
Yong-bum Kim, Seoul, KR;
Yong-Bum Kim, Seoul, KR;
Abstract
The present invention relates to a method for production of terephthalic acid using high polymerization degree polyethylene terephthalate, which includes: (i) introducing high polymerization degree polyethylene terephthalate having an intrinsic viscosity of 0.75 dl/g or more into a continuous reactor, and then heating and pressurizing the same to prepare a fluidal polyethylene terephthalate; (ii) introducing a mixed slurry prepared by mixing an alkaline material containing an alkali-metal, a weak acid salt of the alkali-metal and ethylene glycol together into an internal position of the continuous reactor, through which the fluidal polyethylene terephthalate passes, and implementing neat reaction of the fluidal polyethylene terephthalate with the mixed slurry in the continuous reactor to prepare alkali-metal terephthalate; and (iii) dissolving the prepared alkali-metal terephthalate in water, removing foreign substances through filtration and centrifugation, adding acid to the alkali-metal terephthalate dissolved in water and reacting the same, thereby producing terephthalic acid.