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BACKGROUND Propane dehydrogenation is an alternative way both to produce propylene and to utilize CO2. Because of the high oxygen mobility in cerium‐zirconium oxide (CexZr1‐xO2), it looks promising as a support for the chromium oxide catalysts of propane dehydrogenation with CO2. Supports of CexZr1‐xO2 on mesoporous silica were synthesized in this work to combine the high oxygen mobility of the former and the pore structure of the latter. RESULTS Two applied synthetic approaches resulted in materials with different structure and properties. The wet impregnated catalysts demonstrated a higher activity and selectivity to propylene. At the same time, they had larger pore size distribution maxima (~9 nm) than the samples prepared by the introduction of metals simultaneously with Si‐precursor hydrolysis (~2 nm). For the chromium catalysts with the same support, the catalytic activity decreased with varying chromium loading as follows: 5% Cr > 3% Cr ≈ 7% Cr. For the catalysts with different CexZr1‐xO2 supports and equal chromium loading, the activity decreased with x changing as follows: 0.5 > 0.6 > 0.8 for the samples prepared by wet impregnation, and 0.8 ≈ 0.6 > 0.5 for the other synthetic path. CONCLUSIONS Catalysts were tested in oxidative dehydrogenation of propane with CO2. The wet impregnation approach turned out to be much more promising in terms of catalytic activity and selectivity to propylene in the reaction of propane dehydrogenation with CO2. The selectivity achieved was ≤80% at a 40% conversion. © 2023 Society of Chemical Industry (SCI).

Because of the growing demand for high-quality fuels, the light cycle oil fraction improvement including cetane number improvement is important. The main way to reach this improvement is the ring opening of cyclic hydrocarbons, and a highly effective catalyst should be found. Cyclohexane ring openings are a possible option to investigate the catalyst activity. In this work, we investigated rhodium-loaded catalysts prepared using the commercially available industrial supports: single-component ones, SiO2 and Al2O3; and mixed oxides CaO + MgO + Al2O3 and Na2O + SiO2 + Al2O3. The catalysts were prepared by incipient wetness impregnation and investigated by N2 low-temperature adsorption-desorption, XRD, XPS, DRS UV-Vis and DRIFT spectroscopy, SEM, and TEM with EDX. The catalytic tests were performed in cyclohexane ring opening in the range of 275–325 °C. The best result was demonstrated by the sample 1Rh/CaMgAlO: the selectivity to n-hexane was about 75% while the cyclohexane conversion was about 25% at 275 °C. The space-time yield was up to 12 mmoln-hexane gcat−1h−1.