Alumina and silica supported Ce-Fe-O systems obtained by the solution combustion method and their performance in CO2 hydrogenation to syngas

Abstract

This study presents Ce-Fe-O systems supported on γ-Al 2 O 3 or SiO 2 to enhance the reactivity of an oxygen-deficient CeFeO 3 perovskite phase, which are promising catalysts for the production of fuels and chemicals from CO 2 as feedstock. The synthesis was carried out by the glycine-nitrate solution combustion method at various fuel-to-oxidizer ratios, and with or without the addition of ammonium nitrate. The obtained composites were characterized by XRD, SEM, EDX, N 2 -physisorption, H 2 -TPR, and CO 2 -TPD to study the relationship of physicochemical properties with catalytic CO 2 hydrogenation (rWGS) activity. γ-Al 2 O 3 was found to be a more suitable support than SiO 2 due to its ability to form a higher content of the perovskite phase, significantly reduce the size of CeFeO 3 crystallites, and increase oxygen defectiveness and CO 2 adsorption capacity. Combustion in the presence of silica results in the binding of most of cerium into a silicate phase, which is inactive for rWGS. KEYWORDS perovskites, cerium orthoferrite, CeFeO 3 , alumina, silica, solution combustion synthesis, glycine, carbon dioxide, CO 2 hydrogenation, rWGS ACKNOWLEDGEMENTS This research was funded by the Russian Science Foundation (grant number 22-23-20094, https://rscf.ru/project/22-23-20094/, accessed on 26 October 2023) and the St.-Petersburg Science Foundation (agreement number 26/2022 from 14 April 2022). FOR CITATION Matveyeva A.N., Omarov S.O., Gavrilova M.A. Alumina and silica supported Ce-Fe-O systems obtained by the solution combustion method and their performance in CO 2 hydrogenation to syngas.