Ligand-Aided Glycolysis of PET Using Functionalized Silica-Supported Fe2O3 Nanoparticles
Casey, Éadaoin (University College Cork. Environmental Research Institute)
Breen, Rachel (University College Cork. Environmental Research Institute)
Gómez, Jennifer S. (Radboud University. Institute for Molecules and Materials)
Kentgens, Arno P. M. (Radboud University. Institute for Molecules and Materials)
Pareras Niell, Gerard (Universitat Autònoma de Barcelona. Departament de Química)
Rimola Gibert, Albert (Universitat Autònoma de Barcelona. Departament de Química)
Holmes, Justin. D. (University College Cork. Environmental Research Institute)
Collins, Gillian (University College Cork. Environmental Research Institute)

Date:	2023
Abstract:	The development of efficient catalysts for the chemical recycling of poly(ethylene terephthalate) (PET) is essential to tackling the global issue of plastic waste. There has been intense interest in heterogeneous catalysts as a sustainable catalyst system for PET depolymerization, having the advantage of easy separation and reuse after the reaction. In this work, we explore heterogeneous catalyst design by comparing metal-ion (Fe3+) and metal-oxide nanoparticle (Fe2O3 NP) catalysts immobilized on mesoporous silica (SiO2) functionalized with different N-containing amine ligands. Quantitative solid-state nuclear magnetic resonance (NMR) spectroscopy confirms successful grafting and elucidates the bonding mode of the organic ligands on the SiO2 surface. The surface amine ligands act as organocatalysts, enhancing the catalytic activity of the active metal species. The Fe2O3 NP catalysts in the presence of organic ligands outperform bare Fe2O3 NPs, Fe3+-ion-immobilized catalysts and homogeneous FeCl3 salts, with equivalent Fe loading. X-ray photoelectron spectroscopy analysis indicates charge transfer between the amine ligands and Fe2O3 NPs and the electron-donating ability of the N groups and hydrogen bonding may also play a role in the higher performance of the amine-ligand-assisted Fe2O3 NP catalysts. Density functional theory (DFT) calculations also reveal that the reactivity of the ion-immobilized catalysts is strongly correlated to the ligand-metal binding energy and that the products in the glycolysis reaction catalyzed by the NP catalysts are stabilized, showing a significant exergonic character compared to single ion-immobilized Fe3+ ions.
Grants:	European Commission 101008500 Agencia Estatal de Investigación PID2021-126427NB-I00
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Heterogeneous catalysts ; Glycolysis ; SiO2 ; Nanoparticles ; Polyethylene terephthalate ; DFT ; Solid-state NMR
Published in:	ACS sustainable chemistry & engineering, Vol. 11, Issue 43 (October 2023) , p. 15544-15555, ISSN 2168-0485

DOI: 10.1021/acssuschemeng.3c03585
PMID: 37920799

12 p, 7.1 MB

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