| Title |
Structure-Property Relationships for Nickel Aluminate Catalysts in Polyethylene Hydrogenolysis with Low Methane Selectivity |
| ID_Doc |
25198 |
| Authors |
Vance, BC; Najmi, S; Kots, PA; Wang, C; Jeon, S; Stach, EA; Zakharov, DN; Marinkovic, N; Ehrlich, SN; Ma, L; Vlachos, DG |
| Title |
Structure-Property Relationships for Nickel Aluminate Catalysts in Polyethylene Hydrogenolysis with Low Methane Selectivity |
| Year |
2023 |
| Published |
|
| Abstract |
Earth-abundant metals have recently been demonstratedas cheapcatalyst alternatives to scarce noble metals for polyethylene hydrogenolysis.However, high methane selectivities hinder industrial feasibility.Herein, we demonstrate that low-temperature ex-situ reduction (350 & DEG;C) of coprecipitated nickel aluminate catalysts yields a methaneselectivity of <5% at moderate polymer deconstruction (25-45%).A reduction temperature up to 550 & DEG;C increases the methane selectivitynearly sevenfold. Catalyst characterization (XRD, XAS, Al-27 MAS NMR, H-2 TPR, XPS, and CO-IR) elucidates the complexprocess of Ni nanoparticle formation, and air-free XPS directly afterreaction reveals tetrahedrally coordinated Ni2+ cationspromote methane production. Metallic and the specific cationic Niappear responsible for hydrogenolysis of internal and terminal C-Cscissions, respectively. A structure-methane selectivity relationshipis discovered to guide the design of Ni-based catalysts with low methanegeneration. It paves the way for discovering other structure-propertyrelations in plastics hydrogenolysis. These catalysts are also effectivefor polypropylene hydrogenolysis. |
| PDF |
https://pubs.acs.org/doi/pdf/10.1021/jacsau.3c00232
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