Rare-earth orthoferrites have found wide application in thermocatalytic reduction-oxidation processes. Much less attention has been paid, however, to the production of CeFeO3, as well as to the study of its physicochemical and catalytic properties, in particular, in the promising process of CO2 utilization by hydrogenation to CO and hydrocarbons. This study presents the results of a study on the synthesis of CeFeO3 by solution combustion synthesis (SCS) using various fuels, fuel-to-oxidizer ratios, and additives. The SCS products were characterized by XRD, FTIR, N2-physisorption, SEM, DTA–TGA, and H2-TPR. It has been established that glycine provides the best yield of CeFeO3, while the addition of NH4NO3 promotes an increase in the amount of CeFeO3 by 7–12 wt%. In addition, the synthesis of CeFeO3 with the participation of NH4NO3 makes it possible to surpass the activity of the CeO2–Fe2O3 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 FeOx nanoparticles on the surface of crystallites, and an increase in the surface defects. CeFeO3 obtained in this study allows for achieving higher CO2 conversion compared to LaFeO3 at 600 °C.

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Dehydrogenation of isobutane to isobutene over supported gallium oxide microspherical catalysts was investigated in a fluidized-bed reactor. A partially crystallized nanostructured aluminum hydroxide-oxide, which is a product of gibbsite centrifugal thermal activation (CTA) obtained using a CEFLAR technology, was used as a catalyst support. The structural and textural properties of Ga2O3/Al2O3 catalysts were characterized by a range of techniques including XRD, N2-physisorption, TPD of NH3 and CO2, IRS of adsorbed pyridine, and selective adsorption of a series of acid–base indicators. A Ga–Al oxide catalyst exhibited a stable performance close to activity of Cr–Al oxide catalysts not containing soluble hexavalent chromium. Upon addition of Cr2O3 (6 wt % of Cr), in amounts lower than in an industrial chromia/alumina catalyst (10.9% Cr), and 1% ZrO2 to 6%Ga/Al2O3 catalytic activity in isobutane dehydrogenation reaches the performance of the industrial KDM catalyst (“Sintez”, Russia).

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