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The structures of porous ceramic membrane catalytic systems exhibiting high activity in dry reforming of biomass conversion products (methane, hydrocarbons C2–C4, and alcohols) to a hydrogen-containing gas were studied. The membrane catalytic systems represent porous inorganic membranes (supports) prepared by self-propagating high-temperature synthesis and modified by nanosized metallocompex components, which are uniformly distributed in the internal pore volume. Structural studies were carried out using scanning electron microscopy with energy dispersive analysis, transmission electron microscopy, temperature-programmed reduction with hydrogen, and X-ray diffraction analysis.

A method of high-performance dry reforming of methane into syngas at temperatures below 650 °C on membrane catalytic systems was proposed. The membrane catalytic systems consist of porous inorganic membrane-supports, prepared by self-propagating high-temperature synthesis and modified by nanosized metallocomplex components, which are uniformly distributed inside membrane pores. The influence of the composition of the supported active components, temperature, and flow rate on the activity and selectivity of CH4 and CO2 transformations into syngas, as well as the dynamics of CH4 and CO2 conversion on the membrane catalytic systems were studied.

Ceramic and cermet membranes containing catalytic coatings in the internal volume of their channels were obtained. A relationship between the permeability and kinetic regularities of CO oxidation describing the transmembrane flow of gases was studied. The pre-exponential factor and apparent activation energy change as the loading of the membrane channels by the catalyst proceeds. The study of gas permeability through the membranes showed that the catalyst with a loose branched surface is distributed in the membrane microchannels. The reaction rate constant increases in parallel with an increase in the relative fraction of the catalyst surface. The CO oxidation rate is assumed to depend statistically on the number of active sites, which increases with filling of the membrane channels by the catalytic material.

With the aim of elucidating the mechanism of the thermochemical conversion of oligophenylenes containing acenaphthylenyl groups, the thermolysis of model compounds: l,3,5-tris(5-acenaphthylenyl)benzene (1), 1,3,5-tris(5-acenaphthenyl)benzene (2), acenaphthylene, and acenaphthene, was studied by differential thermal analysis (DTA), dynamic thermogravimetric analysis (TGA), and mass spectrometry. Compounds1 and2 were studied by X-ray structural analysis. A scheme for the formation of secondary structures was suggested. Optimum temperature conditions were found for preparing thermostable, heat-resistant, and stable to thermooxidation polymers based on compounds containing the acenaphthylenyl groups.

A novel carborane-containing compound with ethynyl groups, 1,2-bis[4-(4′-ethynylphenoxy)phenyl]-o-carborane, was synthesized. Cross-linking with 4-iodo- and 4,4′-diiododiphenyl ethers catalyzed by Pd complexes afforded the model bis-arylene ethynylenes and the corresponding polymers. The introduction of a carborane nucleus into the structure of the model compounds and polymers was shown to render these systems soluble.

Synthesis and X-ray structural investigation of 1,3,5-tris[4-(2-propynyloxy)phenyl]benzene (1) were carried out. Compound1 is a trifunctional monomer for the synthesis of cross-linked polymers and a model of a section of polymeric network of this kind. In a crystal, the molecule of1 is located on the threefold symmetry axis and has a propeller-like conformation (the dihedral angle between the central and peripheral benzene rings is ∼35°). An essential feature of the crystal structure of1 is the proximity of the ethynyl groups of the neighboring molecules, which may be favorable to cyclotrimerization in the crystal. The spatial prerequisite to this process is the simultaneous rotation of the neighboring molecules1 about their symmetry axes by ∼10°. The displacements of the atoms in the reacting groups should amount to ∼1.6–1.8 A.

The chemical heterogeneity of polyphenylenes obtained by trimerization poiycycio-condensation of acetylaromatic compounds has been investigated by GLC-MS analysis of the products of trimerization cyclocondensation of acetophenone. The mechanism for the formation of side products of the reaction is discussed. The presence of dypnone fragments in the polyphenylene structure results in a decrease in the thermal stability of these polymers.