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Pt/Sup catalysts with SiO2, MCM-48, and Al2O3 supports (Sup) were prepared. The catalysts were studied by methods of low-temperature nitrogen adsorption, temperature-programmed reduction, and high-resolution transmission electron microscopy. The kinetic characteristics of hydrogenation of biphenyl and diphenylmethane taken separately and of their eutectic mixture were studied on a flow-through catalytic installation at temperatures of 150–170°С, pressure of 4 MPa, liquid hourly space velocity (LHSV) of 5–15 h–1, and hydrogen/feed ratio of 500 m3n.c./m3. A biphenyl–diphenylmethane eutectic mixture (weight ratio 35 : 65) was used as a model mixture. According to the data obtained, the catalyst activity decreases in the order Pt/MCM-48 > Pt/Al2O3 > Pt/SiO2. The use of mesostructured silicate MCM-48 as a support allows the dispersity of the active phase to be increased compared to the traditional SiO2 and Al2O3, which enhances the catalyst activity in hydrogenation of biphenyl and diphenylmethane. [ABSTRACT FROM AUTHOR]

Pt catalysts supported on the commonly used supports Al2O3, SiO2 and on mesostructured silicates SBA-15 and MCM-48 were examined in the dehydrogenation of decalin, that is the promising liquid organic hydrogen carrier (LOHC). Synthesized catalysts were studied by low-temperature nitrogen adsorption, temperature programmed reduction, high-resolution transmission electron microscopy. The catalysts are characterized by various dispersion of platinum. The activity of catalysts in decalin dehydrogenation decreases in the following order Pt/MCM-48 > Pt/SBA-15 > Pt/SiO2 > Pt/Al2O3. Pt/MCM-48 catalyst allows to release hydrogen in the decalin amount of 5.7 wt% and can be considered the promising LOHC hydrogen storage technology. [ABSTRACT FROM AUTHOR]

Ni/Sup catalysts were prepared, where SBA-15, γ-Al2O3, SiO2 were used as supports (Sup). The synthesized catalysts were investigated by the methods of low-temperature nitrogen adsorption, temperatureprogrammed reduction (TPR), and high-resolution transmission electron microscopy. The catalytic properties of the prepared catalysts were tested in liquid phase hydrogenation of biphenyl under conditions of a flow installation at temperatures of 60-100°C, pressure of 4 MPa, volumetric feed rate of 4-10 h-1 and H2: feed ratio of 1500 nM.. A 1 wt % solution of biphenyl in heptane, as a model mixture, was used. It has been established that the activity of nickel hydrogenation catalysts depends on the nickel content and the type of support. The activity of supported nickel catalysts decreases in the series Ni-12/SBA-15 > Ni-12/SiO2 >> Ni-12/Al2O3. The kinetic characteristics of the biphenyl hydrogenation reaction were determined: the rate constants and activation energy for the hydrogenation of the first and second aromatic rings of the substrate molecule. [ABSTRACT FROM AUTHOR]