Oxidation of 5-hydroxymethylfurfural (HMF), a major feedstock derived from waste/fresh biomass, into 2,5-furandicarboxylic acid (FDCA) is an important transformation for the production of biodegradable plastics. Herein, we investigated the effect of the support (unmodified and modified titania, commercial alumina, and untreated and treated Sibunit carbon) of mono- and bimetallic catalysts based on noble metals (Ag, Au, Pd) on selective HMF oxidation with molecular oxygen to FDCA under mild and basic reaction conditions. The higher selectivity to FDCA was obtained when metals were supported on Sibunit carbon (Cp). The order of noble metal in terms of catalyst selectivity was: Ag < Au < Pd < PdAu. Finally, FDCA production on the most efficient PdAu NPs catalysts supported on Sibunit depended on the treatment applied to this carbon support in the order: PdAu/Cp < PdAu/Cp-HNO₃ < PdAu/Cp-NH₄OH. These bimetallic catalysts were characterized by nitrogen adsorption-desorption, inductively coupled plasma atomic emission spectroscopy, high resolution transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Hammet indicator method and X-ray photoelectron spectroscopy. The functionalization of Sibunit surface by HNO₃ and NH₄OH led to a change in the contribution of the active states of Pd and Au due to promotion effect of N-doping and, as a consequence, to higher FDCA production. HMF oxidation catalyzed by bimetallic catalysts is a structure sensitive reaction.

The transformations of oil components from the Zyuzeevskoye field during catalytic aquathermolysis in the presence of a nickel-containing catalyst precursor and hydrogen donors were studied. It was found that the yield of gasoline and diesel fractions increased by more than 36% in the case of catalytic aquathermolysis in the presence of tetralin. The maximum conversion of asphaltenes was achieved with a simultaneous slowing down of coke formation by four times. The calculation of the structural-group parameters of initial asphaltenes and the products of thermal cracking and catalytic aquathermolysis was made, and the hypothetical construction of their molecular structures was proposed. It was established that the phase composition, ratio, and morphology of nickel catalysts after catalytic aquathermolysis (CA) and catalytic aquathermolysis with tetralin (CA+T) depend on the amount of “free” hydrogen and are represented by Ni_0.96S and Ni₉S₈.

Catalytic reduction of nitroaromatic compounds (NCs) into corresponding aminoaromatic compounds (ACs) addresses two challenges: enhancing of the manufacture scale of ACs as valuable chemical intermediates and removal of NCs as widespread wastewater pollutants. Among the noble metal catalysts that feature low-temperature activity, chemical stability, and nontoxicity, silver-containing catalysts are attractive as cost-efficient and easily prepared compositions. This paper is devoted to the design and study of efficient and environmentally benign Ag- and CeO₂-containing NCs reduction catalysts supported on graphene oxide (GO). The silver- and/or ceria-containing catalysts are synthesized using deposition-precipitation onto GO prepared by oxidative treatment of graphite. The catalysts and support are characterized by XRD, XPS, TGA, N₂ sorption, Raman spectroscopy, and UV–VIS spectrometry. The influence of state and the interaction of the active components on catalytic activity is thoroughly estimated in 4-nitrophenol (4-NP) reduction into 4-aminophenol (4-AP) at ambient pressure and room temperature. Nanosized Ag and CeO₂ particles with sizes up to 30 and 5 nm, respectively, in the GO structure are obtained. The co-deposition of Ag and CeO₂ onto GO promotes the stabilization of silver in the catalyst. The Ag-CeO₂/GO catalyst demonstrates superior activity in the synthesized series (k_app of 1.615 and 3.674 min⁻¹ for as-prepared and pre-reduced samples). In addition, the Ag-CeO₂/GO catalyst retains good stability and a low leaching degree of the active components that makes these compositions efficient in NCs’ reduction into corresponding ACs.