CeFeO[sub.3]–CeO[sub.2]–Fe[sub.2]O[sub.3] Systems: Synthesis by Solution Combustion Method and Catalytic Performance in CO[sub.2] Hydrogenation

• Published in: Materials Vol. 15; no. 22
• Main Authors: Matveyeva, Anna N, Omarov, Shamil O, Gavrilova, Marianna A, Sladkovskiy, Dmitry A, Murzin, Dmitry Yu
• Format: Journal Article
• Language: English
• Published: MDPI AG 01.11.2022
• Subjects: Catalysis; Combustion; Energy minerals; Fossil fuels; Hydrogenation; Methods; Japan; Russia
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma15227970

Rare-earth orthoferrites have found wide application in thermocatalytic reduction-oxidation processes. Much less attention has been paid, however, to the production of CeFeO[sub.3], as well as to the study of its physicochemical and catalytic properties, in particular, in the promising process of CO[sub.2] utilization by hydrogenation to CO and hydrocarbons. This study presents the results of a study on the synthesis of CeFeO[sub.3] by solution combustion synthesis (SCS) using various fuels, fuel-to-oxidizer ratios, and additives. The SCS products were characterized by XRD, FTIR, N[sub.2]-physisorption, SEM, DTA-TGA, and H[sub.2]-TPR. It has been established that glycine provides the best yield of CeFeO[sub.3], while the addition of NH[sub.4]NO[sub.3] promotes an increase in the amount of CeFeO[sub.3] by 7-12 wt%. In addition, the synthesis of CeFeO[sub.3] with the participation of NH[sub.4]NO[sub.3] makes it possible to surpass the activity of the CeO[sub.2]-Fe[sub.2]O[sub.3] system at low temperatures (300-400 °C), as well as to increase selectivity to hydrocarbons. The observed effects are due to the increased gas evolution and ejection of reactive FeO[sub.x] nanoparticles on the surface of crystallites, and an increase in the surface defects. CeFeO[sub.3] obtained in this study allows for achieving higher CO[sub.2] conversion compared to LaFeO[sub.3] at 600 °C.