Kinetic Phenomena in Mechanochemical Depolymerization of Poly(styrene).
ACS Sustain Chem Eng
; 12(1): 178-191, 2024 Jan 08.
Article
em En
| MEDLINE
| ID: mdl-38213546
ABSTRACT
Synthetic polyolefinic plastics comprise one of the largest shares of global plastic waste, which is being targeted for chemical recycling by depolymerization to monomers and small molecules. One promising method of chemical recycling is solid-state depolymerization under ambient conditions in a ball-mill reactor. In this paper, we elucidate kinetic phenomena in the mechanochemical depolymerization of poly(styrene). Styrene is produced in this process at a constant rate and selectivity alongside minor products, including oxygenates like benzaldehyde, via mechanisms analogous to those involved in thermal and oxidative pyrolysis. Continuous monomer removal during reactor operation is critical for avoiding repolymerization, and promoting effects are exhibited by iron surfaces and molecular oxygen. Kinetic independence between depolymerization and molecular weight reduction was observed, despite both processes originating from the same driving force of mechanochemical collisions. Phenomena across multiple length scales are shown to be responsible for differences in reactivity due to differences in grinding parameters and reactant composition.
Texto completo:
1
Bases de dados:
MEDLINE
Idioma:
En
Revista:
ACS Sustain Chem Eng
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos