Two series of Pt/γ-Al 2 O 3 catalysts for low temperature NH 3 oxidation were prepared using Pt(NO 3 ) 4 and H 2 PtCl 6 precursors. Using both precursors results in the formation of small Pt particles (d < 1.5 nm), however, Cl-containing Pt precursors give a higher fraction of highly dispersed Pt species. Such species show high stability against thermal or H 2 treatment probably due to the presence of a substantial amount of chlorine on the surface. Treatment of the samples prepared from Pt(NO 3 ) 4 with H 2 leads to the formation of metallic Pt nanoparticles accompanied by the improvement of catalytic activity in NH 3 oxidation at T < 200°C. The main products of ammonia oxidation at temperatures below 250°C were molecular nitrogen and nitrous oxide with the N 2 selectivity reaching 80 %. Operando XANES/ EXAFS revealed that even after H 2 pretreatment at least 40 % of Pt surface remains in oxidized state under reaction conditions resulting in the appearance of N 2 O as a by-product.

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NAP-XPS and operando XAS study of Pt/TiO2 catalysts shows that Pt0 species stabilized on TiO2 surface have the highest activity at low-temperature NH3 oxidation.

Catalytic hydrogenation of vegetable oils was studied over Pd nanocomposite carbon catalysts. The mesoporous structure of the carbon support was beneficial to achieve fast hydrogenation rates and the desired cis/trans ratio of monoenic products of edible oil hydrogenation. The preparation procedure developed for a slurry catalyst was successfully utilized for fixed bed applications. Industrial experience of Pd/nanocomposite carbon utilization in selective hydrogenation of edible and total hydrogenation of nonedible oils is described.