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MnOx-CeO2, MnOx-ZrO2, MnOx-ZrO2-CeO2 oxides with the Mn/(Zr + Ce + Mn) molar ratio of 0.3 were synthesized by coprecipitation method followed by calcination in the temperature range of 400–800 °C and characterized by XRD, N2 adsorption, TPR, TEM, and EPR. The catalytic activity was tested in the CO oxidation reaction. It was found that MnOx-CeO2, MnOx-ZrO2-CeO2, MnOx-ZrO2 catalysts, calcined at 400–500 °C, 650–700 °C and 500–650 °C, respectively, show the highest catalytic activity in the reaction of CO oxidation. According to XRD and TEM results, thermal stability of catalysts is determined by the temperature of decomposition of the solid solution Mnx(Ce,Zr)1−xO2. The TPR-H2 and EPR methods showed that the high activity in CO oxidation correlates with the content of easily reduced fine MnOx particles in the samples and the presence of paramagnetic defects in the form of oxygen vacancies. The maximum activity for each series of catalysts is associated with the start of solid solution decomposition. Formation of active phase shifts to the high-temperature region with the addition of zirconium to the MnOx-CeO2 catalyst.

Hydrodeoxygenation of sunflower oil on M/WO3−Al2O3 (M = NiMo, Pt, Pd, Ni) catalysts prepared by incipient wetness impregnation was investigated. The metal deposited on WO3-Al2O3 affects the main directions of the conversion of raw materials, and, consequently, the yield and composition of the products. The low dispersion of monometallic catalysts and high Bronsted acidity promote oxygen removal along the direct hydrodeoxygenation (HDO) route. Unlike monometallic systems, triglyceride hydrocracking on NiMoS/WO3-Al2O3 catalysts proceeds with the formation of propane as the main by-product. The high activity of the NiMoS/WO3-Al2O3 catalyst in hydrogenation and decarbonylation/decarboxylation (deCOx) reactions results in lower yields of liquid hydrocarbon product.

A series of propylene metathesis MoO3/Al2O3 catalysts (2–10 wt. % of MoO3) activated in Ar and under ex situ reaction conditions was studied by EPR spectroscopy. Similar EPR signals from surface molybdate clusters (Mo5+) were observed for each sample. The concentration of pentavalent molybdenum in paramagnetic form determined by EPR increases with an increase in the MoO3 content from 2 to 5 wt. %, then changes slightly. It was also found that the activity of the catalysts in the propylene metathesis reaction is proportional to the increment in the concentration of Mo5+ paramagnetic species determined after contact with propylene. This indicates that higher oxidation states of molybdenum form active paramagnetic complexes during the reaction with propylene.

The structural changes taking place in high (P-267E) and low (T-900) dispersion carbon blacks under the high energy electron beam irradiation were investigated by EPR spectroscopy. All types of defective paramagnetic structures formed during the irradiation process of the carbon materials were identified. For both samples formation of new paramagnetic defects is occurred, which are due to the decrease of particles size, conjugation (delocalization) of electrons and the length of graphene layers in general.