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Commercial carbon black (CB) was mechanically activated in air for 5–60 min and 100 g acceleration of milling bodies, which were represented by steel balls with the diameter of 2, 5 and 8 mm. Changes in the composition and structure of the tested objects, including their surface layers, were considered. IR spectroscopy and acid-base titration showed that mechanical activation (MA) of CB results in the formation of oxygen-containing surface functional groups in the amount of 0.21–0.34 mEq/g. The analysis of the pore texture of mechanically activated CB samples revealed that an increase in MA intensity increases the specific surface area and decreases the total pore volume. The high intensity of MA leads to the formation of the pore system in CB that differs from the initial system and consists of 10–100 nm pores and thin pores with the size of 3–5 nm. A TEM study on the morphology of mechanically activated CB samples demonstrated that activation at the high intensity results in the partial destruction of globules and the appearance of small particles with the size of 2–5 nm. A structural study showed that mechanical activation at the high intensity may lead to rearrangement of graphene layers in globules.

High surface area carbon aerogels with increasing molybdenum content were obtained by carbonization of resorcinol–formaldehyde polymer aerogels after incipient wetness impregnation (IWI). The Mo(VI) form of the impregnant was converted into different molybdenum species during the heat treatment, resulting in samples with substantially different surface and bulk compositions. The samples were tested in the hydroconversion reaction of acetic acid, a model biomass. The reaction pathways and the product distribution were governed by the accessibility of the carbon surface as well as by the amount and form of Mo. The highest selectivity for ethanol was 16%, when 85% of the acetic acid was converted. Post-catalyst analysis of the aerogels revealed that their morphology and chemistry changed substantially during the redox processes. The products of each of the three potential pathways (hydrogenolysis, ketonization and consecutive reduction) oxidized the surface even in the reductive hydrogen flow.

Porous amorphous silica obtained by the sol–gel method with poly(ethylene glycol) (PEG) as structure directing agent is investigated. In this paper, we use the PEG with molecular weight 400, 1300, 3000, 6000, 20,000, 100,000, 200,000 and vary the concentration of the polymer solution in a wide range. The analysis of nitrogen adsorption–desorption data and transmission electron microscopy shows that depending on the combination of molecular weight and concentration of the PEG solution the microporous and mesoporous silica materials can be obtained. It was determined that using the solution of PEG-400, 1300 independently of the concentration the mesoporous silica is formed. When the diluted and concentrated solutions of PEG-3000, 6000, 20,000, 100,000, 200,000 are used it produces also the mesoporous materials. In the field of transitional concentrations of PEG the microporous silica with fraction of micropores equals 95% is generated. Revealed regularities are generalized and shown on the texture diagram.