One-pot methanolysis of poly(ethylene terephthalate) enabled by isopropanol-assisted CO2 hydrogenation
Journal
Journal of the Taiwan Institute of Chemical Engineers
Date Issued
2023-01-01
Author(s)
Abstract
Background: Recently the plastic pollution and CO2 emission have both become critical issues to be addressed for the sake of a sustainable and carbon-neutral society. To cope with these imminent issues, it is imperative to develop new processes to recycle and reutilize the waste plastics and CO2 produced by anthropogenic activities. Methods: In this study, the chemical recycling of poly(ethylene terephthalate) (PET) was conducted via a one-pot process, in which PET was degraded into dimethyl terephthalate (DMT) and ethylene glycol (EG) by methanol (MeOH) that was in-situ produced by CO2 hydrogenation over the Cu/ZnO catalyst. The effect of alcohol addition on the one-pot PET methanolysis was investigated in an attempt to enhance the MeOH and DMT yields. Significant findings: Our results reveal that the added isopropanol (i-PrOH) could act as a catalytic solvent to boost the PET degradation (from 31.9% to 63.1% PET conversion) with a high DMT selectivity (92.7%) from the CO2-H2-PET system. Such high DMT selectivity is attributed to the limited PET alcoholysis and DMT transesterification ability of i-PrOH. These findings demonstrate that the one-pot PET methanolysis enabled by i-PrOH-assisted CO2 hydrogenation is a promising approach to valorize waste PET and CO2 simultaneously with a high efficiency.
Subjects
Catalytic solvent | CO hydrogenation 2 | Methanolysis | Poly(ethylene terephthalate)
Type
journal article