Synthesis of Ce_xZr_1‐xO₂/SiO₂ supports for chromium oxide catalysts of oxidative dehydrogenation of propane with carbon dioxide

Abstract

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).

Mesoporous Chromium Catalysts Templated on Halloysite Nanotubes and Aluminosilicate Core/Shell Composites for Oxidative Dehydrogenation of Propane with CO2

“…Recently, mesoporous organo-silica has been investigated as a support of CO 2 -assisted ethane dehydrogenation [46]. Mesoporous silica was doped with Ce x Zr 1-x O 2 to promote oxygen mobility [47].…”

CO2-Assisted Sugar Cane Gasification Using Transition Metal Catalysis: An Impact of Metal Loading on the Catalytic Behavior

“…Moreover, CO 2 is a higher oxidation state of carbon atom and can be applied as a mild oxidant in a series of the processes such as carbon materials gasification (Equation (1)), alkanes dehydrogenation, etc. Its application in this role was widely described in the literature [ 2 , 3 , 4 , 5 ]. Thus, it seems reasonable to try to apply CO 2 as an oxidant to the process of CO 2 -assisted gasification of carbon wastes [ 6 ].…”