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The article presents the results of comparative research on the physicochemical characteristics and catalytic activity of copper oxide supported on synthetic SiO2 and SiO2 (RH) from rice husk. SiO2 (RH) is more hydrophobic compared to SiO2, which leads to the concentration of copper oxide on its surface in the form of a "crust", which is very important in the synthesis of low-percentage catalysts. According to SEM, XRD, and TPR-H2, the use of SiO2 (RH) as a carrier leads to an increase in the dispersion of copper oxide particles, which is the active center of ethanol dehydrogenation. [ABSTRACT FROM AUTHOR]

The effect of modifying additives (Ni, La, Ce oxides) on the activity of Cu/Al2O3 with a low copper loading was studied for ethanol non‐oxidative dehydrogenation. The catalysts were prepared by impregnation of the commercial Al2O3 granules and characterized by Brunauer‐Emmett‐Teller (BET), scanning electron microscopy (SEM), temperature‐programmed desorption of NH3 (TPD‐NH3), temperature‐programmed reduction of H2 (H2‐TPR), and thermogravimetric analysis (TGA). Modification of Cu/Al2O3 with Ni, La, and Ce oxides results in increasing catalytic activity. A modification of the Cu/Al2O3 catalyst with nickel and lanthanum oxides, in contrast to cerium oxide, leads to an improvement in the dispersion of the catalyst particles. The Cu‐Ni/Al2O3 catalyst with the highest acidity has the highest selectivity for acetaldehyde. The highest selectivity for butanol is observed for the Cu‐La/Al2O3 catalyst, which has the lowest acidity. [ABSTRACT FROM AUTHOR]

Effective selective catalysts deposited on monolithic metal blocks are developed and tested in reactions of dimethyl ether and diisopropyl ether production at atmospheric pressure from methanol and isopropyl alcohol, correspondingly. The catalysts active phase is based on compounds of Ni, Cu, Mo, W, V and zeolites. The presence of rare-earth elements in the catalysts composition stabilized their activity. The increase of the carrier acidity of the catalyst results in significant increase of iso-propanol transformation, whereas the selectivity in respect to diisopropyl ether decreases slightly. The optimum catalyst composition for diisopropyl ether synthesis is based on molybdenum and nickel compounds. Highly effective stable catalysts providing production of dimethyl ether from methanol with selectivity of 85% - 97% and that of diisopropyl ether from isopropyl alcohol with selectivity of 60% - 69.4% are developed. [ABSTRACT FROM AUTHOR]

The authors discuss the impact of carbon dioxide-based polyether carbonate polyols on the life-cycle of the polymers, and the importance of catalyst-related environmental impacts.