Chemical recycling of polyethylene terephthalate by microwave irradiation
US10858493B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 2019 |
| Grant date | Dec 8, 2020 |
| Priority date | — |
| Expiry date | Oct 24, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process for chemically recycling polyethylene terephthalate (PET) which utilizes a microwave absorber to optimize glycolytic depolymerization of PET via microwave irradiation. The method of chemically degrading PET to its reactive intermediate, bis(2-hydroxyethyl) terephthalate (BHET), is carried out by: (a) combining PET with ethylene glycol and a catalytic system comprising a catalyst and a microwave absorber to produce a heterogeneous reaction mixture; and then (b) heating by microwave irradiating the reaction mixture to a temperature sufficient to produce a reaction product comprising BHET. The BHET monomer then can be purified and re-polymerized to form new, virgin PET.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.