Zn Redistribution and Volatility in ZnZrOx Catalysts for CO2 Hydrogenation

Zn Redistribution and Volatility in ZnZrOx Catalysts for CO2 Hydrogenation

© 2023 The Authors. Published by American Chemical Society.

Bibliographische Detailangaben
Veröffentlicht in:Chemistry of materials : a publication of the American Chemical Society. - 1998. - 35(2023), 24 vom: 26. Dez., Seite 10434-10445
1. Verfasser: Redekop, Evgeniy A (VerfasserIn)
Weitere Verfasser: Cordero-Lanzac, Tomas, Salusso, Davide, Pokle, Anuj, Oien-Odegaard, Sigurd, Sunding, Martin Fleissner, Diplas, Spyros, Negri, Chiara, Borfecchia, Elisa, Bordiga, Silvia, Olsbye, Unni
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2023
Zugriff auf das übergeordnete Werk:Chemistry of materials : a publication of the American Chemical Society
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:© 2023 The Authors. Published by American Chemical Society.
ZnO-ZrO2 mixed oxide (ZnZrOx) catalysts are widely studied as selective catalysts for CO2 hydrogenation into methanol at high-temperature conditions (300-350 °C) that are preferred for the subsequent in situ zeolite-catalyzed conversion of methanol into hydrocarbons in a tandem process. Zn, a key ingredient of these mixed oxide catalysts, is known to volatilize from ZnO under high-temperature conditions, but little is known about Zn mobility and volatility in mixed oxides. Here, an array of ex situ and in situ characterization techniques (scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX), transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), X-ray absorption spectroscopy (XAS), X-ray photoelectron spectroscopy (XPS), Infrared (IR)) was used to reveal that Zn2+ species are mobile between the solid solution phase with ZrO2 and segregated and/or embedded ZnO clusters. Upon reductive heat treatments, partially reversible ZnO cluster growth was observed above 250 °C and eventual Zn evaporation above 550 °C. Extensive Zn evaporation leads to catalyst deactivation and methanol selectivity decline in CO2 hydrogenation. These findings extend the fundamental knowledge of Zn-containing mixed oxide catalysts and are highly relevant for the CO2-to-hydrocarbon process optimization
Beschreibung:Date Revised 03.01.2024
published: Electronic-eCollection
Citation Status PubMed-not-MEDLINE
ISSN:0897-4756
DOI:10.1021/acs.chemmater.3c01632