Value-Added Upcycling of PET to 1,4-Cyclohexanedimethanol by a Hydrogenation/Hydrogenolysis Relay Catalysis.
Angew Chem Int Ed Engl
; : e202408561, 2024 Jun 25.
Article
in En
| MEDLINE
| ID: mdl-38923654
ABSTRACT
We present an innovative process for directly transforming poly(ethylene terephthalate) (PET), a polymer extensively used in food and beverage packaging, into trans-isomer-enriched 1,4-cyclohexanedimethanol (CHDM), a key ingredient in advanced specialty polymers. Our approach leverages a dual-catalyst system featuring palladium on reduced graphene oxide (Pd/r-GO) and oxalate-gel-derived copper-zinc oxide (og-CuZn), utilizing hydrogenation/hydrogenolysis relay catalysis. This method efficiently transforms PET into polyethylene-1,4-cyclohexanedicarboxylate (PECHD), which is then converted into CHDM with an impressive overall yield of 95 % in a two-stage process. Our process effectively handles various post-consumer PET plastics, converting them into CHDM with yields between 78 % and 89 % across different substrates. Additionally, we demonstrate the applicability and scalability of this approach through a temperature-programmed three-stage relay process on a 10-gram scale, which results in purified CHDM with an isolated yield of 87 % and a notably higher trans/cis ratio of up to 4.09/1, far exceeding that of commercially available CHDM. This research not only provides a viable route for repurposing PET waste but also enhances the control of selectivity patterns in multistage relay catalysis.
Full text:
1
Database:
MEDLINE
Language:
En
Journal:
Angew Chem Int Ed Engl
Year:
2024
Type:
Article
Affiliation country:
China