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The effect of a number of burn out additives introduced into the composition of pastes prepared on the basis of aluminum hydroxide, Pural SCF-55, and the modes of sample calcination on the texture and strength parameters of the obtained aluminum oxides has been investigated. The additives are represented by three types of carbon blacks: acetylene, Vulcan XC-72, and Katjenblack EC-300J, as well as ultrafine diamonds, oxidized graphite, egg white, and bovine albumin. It is shown that the introduction of burn out additives affects both the mesoporous and macroporous structure of the support and leads to the formation of transport pores up to 10 μm in size. It has been established that calcining the formed aluminum hydroxide granules, including the considered carbon blacks, in air at 600°C with a preliminary rise in temperature to 450°C in an argon atmosphere makes it possible to obtain Al2O3 with higher crushing strength.

In the current work the activity of Pt/Al2O3 and Pt/TiO2 catalysts in the reaction of NH3 oxidation was studied depending on the calcination temperature. A combination of XRD, TEM, XPS and TPR methods was applied in order to analyze the influence of the interaction between active component and support on the catalytic properties of the samples. Catalysts were prepared by incipient wetness impregnation using the Pt(NO3)4 solution with calcination at 400, 600 and 800°C. A highly dispersed Pt0 particles with the average particles size ∼1 nm were observed after calcination at 400°C for both Pt/Al2O3 and Pt/TiO2 samples. However, Pt/TiO2 catalyst showed better catalytic characteristics at the low-temperature range with the temperature of 50% NH3 conversion (T50) about 175°C. The calcination of the Pt/Al2O3 catalyst at T>400°C improved the low-temperature activity due to the formation of large Pt0 particles. The T50 value did not vary significantly for Pt/TiO2 samples calcined at different temperatures. Based on XPS, XRD and TPR-H2 data the strong metal-support interaction (SMSI) was shown for Pt/TiO2 catalysts. SMSI resulted in the stabilization of platinum in a highly dispersed state even after high temperature calcination. Pt/Al2O3 sample calcined at 800°C had the highest specific catalytic rate of NH3 oxidation. The high activity of the catalyst is likely due to the presence of Pt0 particles with optimal size distribution.