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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Preparation of microspherical chromia−alumina KDM-type catalysts for alkane dehydrogenation is based on utilization of an amorphous nanostructured hydroxide−oxide Al 2 O 3 −x(OH) 2 •nH 2 O (where x = 0−0.28, n = 0.03−1.8) prepared via the centrifugal thermal activation (CTA) of gibbsite. The fine fraction of this carrier is considered as industrial waste, requiring efficient recycling options, which are explored in this work. A range of physicochemical methods was applied to analyze the main properties (phase composition, morphology, reactivity, etc.) of pilot and industrial batches of gibbsite CTA products. It has been clearly shown that the properties of CTA products are dependent on the nature of gibbsite used. The largest amount of the active amorphous phase of alumina is formed using gibbsite made from concentrated nepheline. Regularities of rehydration of the CTA-products fine fraction in acidic/ alkaline media and dissolution in sulfuric acid of the fine fraction of gibbsite and the industrial CTA product were explored to prepare aluminum sulfate, which is a water purification coagulant.

Development of coking resistant supports and catalysts for hydrocarbons conversion is challenging, especially when using such acidic materials as alumina. Apparently, this problem can be mitigated by using spinels that...