Journal
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
Volume 10, Issue 34, Pages 11338-11347Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acssuschemeng.2c03376
Keywords
ball milling; hydrolysis; mechanochemistry; plastics recycling; polymers
Categories
Funding
- Kolon Industries, Inc., through the Kolon Center for Lifestyle Innovation at Georgia Tech
- Emerging Frontiers in Research and Innovation program [2028998]
Ask authors/readers for more resources
In this study, depolymerization of PET using mechanochemical hydrolysis was investigated. The results showed that the monomer yield of PET increased linearly with milling time, while the molecular weight decreased slightly. The influence of ball-to-powder mass ratio and milling frequency on depolymerization was also studied.
Efficient chemical recycling of consumer plastics (i.e., depolyme-rization down to monomers) is a crucial step needed to achieve a circular material economy. In this work, depolymerization of poly(ethylene terephthalate) (PET) via mechanochemical hydrolysis with sodium hydroxide is studied, with complete depolymerization achieved in 20 min. The stages of depolymerization are investigated by monitoring monomer yields and the change in the PET molecular weight over the course of the reaction. The monomer yields initially increase linearly with milling time, up to a yield of roughly 40%. However, the molecular weights of the residual PET decrease concomitantly only slightly, suggesting a reaction scheme analogous to a shrinking core model. As the reaction progresses, a physical transition of the PET/NaOH from a powder to a homogeneous wax and a simultaneous increase in the depolymerization rate are observed. The influence of ball-to-powder mass ratio (BPR) and milling frequency is studied to derive a kinetic rate expression. The linear relationship between BPR and monomer yield and the known relationship between milling frequency are validated for this system.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available