Process for purification of recovered ethylene glycol from chemical recycling of waste polyester

• Main Authors: MATTHEW. FILANOVA, OSOGNO MIGUEL, KOWALSKI MICHAEL, SMITH JASON
• Format: Patent
• Language: Chinese; English
• Published: 28.04.2023
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

There is provided a process for purifying a polyester grade ethylene glycol from a crude ethylene glycol containing at least a first component and a second component, the first and second components having a boiling point lower than the boiling point of ethylene glycol, the process comprising: (a) depolymerizing polyethylene terephthalate in a chemical recycling process, providing a stream of crude ethylene glycol; (b) introducing the crude ethylene glycol stream into a first distillation column for distilling the first component and removing the first component from the process; (c) withdrawing a first stream from a lower portion of the first distillation column and feeding the first stream to a second distillation column for distilling the second component and removing the second component from the process; (d) withdrawing a second stream from a lower portion of the second distillation column and feeding the second stream to a third distillation column; and (e) recovering polyester grade ethylene glycol fro