The nanostructured catalytic membranes consisted of stainless steel porous support modified with carbon layer, and catalytic layer, containing Pt–Ru alloy nanoparticles, homogeneously dispersed in carbon matrix, were synthesized for the first time by IR-pyrolysis method. The optimization of pore size of plates of porous stainless steel was carried out using carbon, prepared by IR-pyrolysis of PAN, introduced in support pores in DMFA solution. The structure and thickness of modifying layer were controlled by PAN initial concentration and IR-annealing intensity. The selectivity of helium–argon pair separation increased monotonously as carbon layer thickness increased. The catalytic layers, based on IR-PAN carbon, Pt–Ru nanoparticles and finely dispersed activated carbon SKT or detonation nanodiamonds, were deposited on carbon modified porous membranes. The selectivity of permeability for pair helium–argon increased after catalytic layer deposition, becoming equal to the ideal Knudsen value. Cyclohexane dehydrogenation on obtained composite metal–carbon membrane catalysts were carried out in plug flow catalytic membrane reactor at the temperatures from 220 to 520°C. The productivity on the unit of mass of active metal of composite membrane metal–carbon catalyst, was shown to be significantly higher than that of the same metal–carbon composites in grained form.

The scientific principles were formulated that underlie an integrated approach to development and synthesis of bulk and membrane catalysts for methanol transformation to dimethyl ether and hydrogen which are environmentally friendly fuels. The results were summarized for studies into relationships in formation of phosphates MZr2(PO4)3 (M = Na, K, Rb, Cs, Mg0.5, Ca0.5, Sr0.5, Ba0.5, Zr0.25), Cu0.5(1+y)Fe y Zr2−y (Po4)3, molybdate phosphates Na1−y Zr2(Moo4) y (Po4)3−y , and molybdate Ni0.3Cr0.4Fe1.4(Moo4)3 with the desired structure and properties controllable by variation of their chemical composition and synthesis parameters. The surface characteristics and catalytic properties of the resulting systems and the yields of the target product formed from methanol transformations in inert and oxidizing atmospheres were analyzed in relation to the catalyst synthesis condition.

Principal approaches for the preparation of catalytic membrane reactors based on polymer membranes containing palladium nanoparticles and for the description of their characteristics are presented. The method for the development of adlayers composed of palladium nanoparticles and their aggregates on the surface of hydrophobic polypropylene porous hollow fiber membranes is proposed, and their comprehensive study is performed. Various regimes of the deposition of palladium on individual fibers and on membrane surface inside membrane modulus are considered. The sizes of primary Pd particles range from 10 to 500 nm, and dimensions of their aggregates vary from 200 nm to tens of microns. The sizes of primary particles in a free state and in their aggregates are estimated by the methods of X-ray analysis and scanning electron microscopy. The proposed approach is used for the preparation of catalytic membrane contactors/reactors for the removal of dissolved oxygen from water. In the systems under study, the limiting stage of dissolved oxygen removal is concerned with diffusion-controlled delivery of oxygen to the surface of catalytic particles.

This survey is devoted to studying the process of modifying the surface of a porous matrix using the molecular layering method and the prospects of its application for controlling the structural, physical, and chemical characteristics of inorganic membranes. Experimental data on the application of molecular layering for the creation of membrane catalytic reactors with its given gas permeability, selectivity, and catalytic activity are discussed. It is demonstrated that such systems can be obtained by applying layers of certain thicknesses, structures, and chemical compositions on the inner surface of membrane pores in one technological cycle.

Electrochemical dimerization of hexafluoropropylene oxide dimer and trimer acids on SU-2000 glassy carbon, bulk platinum, and SU-2000 electrodes modified with platinum-group metals in acetonitrile in the presence of water was studied at various concentrations of the starting substance and different degrees of neutralization of the starting acid. Also, the possibility was examined of obtaining some perfluoropolyethers in a single process by cross-condensation of several starting perfluorocarboxylic acids, followed by separation of the products by physicochemical methods.

Studied in this work were the industrially important processes (partial oxidation of methane, oxidation of methanol to formaldehyde, reduction of oxygen in aqueous media, oxidation of CO to CO2) involving the use of nanostructured catalytic membrane reactors of the new generation. The membrane reactors were prepared according to various methods: sol-gel, molecular layering, magnetron sputtering, chemical deposition, etc. Subject to study were also the structure of the catalytic membranes and the kinetics of the reactions occurring in the gaseous and liquid phases. It was demonstrated that the deposition of a nanostructured catalytic layer to nonselective porous membranes could give rise to, or enhance, the selectivity of both their gas permeability and catalytic activity. In the case of the application of hybrid membranes, an “asymmetry effect” was discovered and explained. Some of the membranes studied can be considered as specific nanoreactors.

The changes in structural characteristics, chemical composition, and gas permeability of the modified ceramic asymmetric tubular membranes were studied. The membranes were tested in permeability and selectivity of two gaseous mixtures (H/He and H/Ar). The structure of the modified coating was examined by X-ray powder diffraction and by transmission and scanning electron microscopies.

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This review briefly analyzes processes for eliminating and recycling polychlorobiphenyls (PCBs), persistent industrial organic pollutants. The potential of chemical processes for PCB recycling via conversion to nontoxic, useful products, such as esters, is inferred from this review. A new process is proposed for recycling PCBs by carbonylation using a new, high-activity catalyst system for activating inert aryl halides. The advantages of this process are low power consumption ( p CO = 0.1–0.3 MPa, T ≤ 65°C) and a low-cost and available precursor (cobalt carbonyl modified by propylene oxide (PO)) in the presence of potassium carbonate and methanol. The reaction products are nontoxic and useful aromatic di- and tricarboxylic acids or their derivatives (salts or esters). The process inhibits the appearance and retention of dioxins in the reaction mixture.

Complex phosphates of titanium, chromium, and metals(2+) of the general formula M 0.5(1 + x) Cr x Ti 2 - x (PO 4 ) 3 (M = Mg, Ca, Mn, Ni, Sr, Ba, and Pb) were synthesized. Their phase formation was studied by means of X-ray powder diffraction, electron probe microanalysis, differential thermal analysis, and IR spectroscopy. Individual phases and solid solutions crystallizing in kosnarite and langbeinite structure types were identified; their crys- tallographic parameters were calculated. The catalytic properties of phosphates Ca0.5(1 + x)CrxTi2 - x(PO4)3 in methanol conversion were studied.

Scanning electron microscopy, X-ray diffraction and adsorption structural analyses, and helium pycnometry were used to study the structure of nanoporous carbon produced by chlorination of powdered titanium carbide and carbonitride and of titanium carbide synthesized by chemical-vapor deposition. The results obtained were used to make suggestions about the type of organization of the nanoporous structure of these materials. The evolution of the structure of nanoporous carbon was analyzed in relation to the chlorination temperature. The effect of the chlorination temperature on the structure of the nanoporous carbon obtained and on its pore volume was examined.

Complex phosphates of titanium, chromium, and metals(2+) of the general formula M 0.5(1 + x )Cr x Ti 2 − x (PO 4 ) 3 (M = Mg, Ca, Mn, Ni, Sr, Ba, and Pb) were synthesized. Their phase formation was studied by means of X-ray powder diffraction, electron probe microanalysis, differential thermal analysis, and IR spectroscopy. Individual phases and solid solutions crystallizing in kosnarite and langbeinite structure types were identified; their crystallographic parameters were calculated. The catalytic properties of phosphates Ca 0.5(1 + x )Cr x Ti 2 − x (PO 4 ) 3 in methanol conversion were studied.

Molybdate phosphates Na1−yZr2(MoO4)y(PO4)3 − y (y = 0, 0.25, 0.5) having the NaZr2(PO4)3 structure were prepared by the sol-gel method. The catalytic properties of the molybdate phosphates in dehydration and dehydrogenation of methanol in inert and oxidizing atmospheres were studied.

The key lines of research in a new field of the membrane science and technology, viz., organic solvent nanofiltration, are considered. The prospects for its use in chemical, petrochemical and food industries are discussed. Attention is focused on membranes developed for this method.

The results of the study of phase formation, structural types, surface properties of the phosphates Cu0.5(1+y)FeyZr2−y(PO4)3 and their catalytic activity in methanol conversion are presented. The samples of phosphates with y=0, 0.5, 1.0, 1.5 and 2.0 were prepared by the precipitating method. The X-ray phase analysis showed that the phosphates within 0≤y≤1.0 form a series of structural analogues belonging to the structural type of Sc2(WO4)3, the compound Cu1.5Fe2(PO4)3 (y=2) crystallizes in the Fe7(PO4)6-type structure, the sample with y=1.5 of the composition Cu1.25Fe1.5Zr0.5P3O12 was phase mixture. It was shown that with an increase in y value (i.e. with a reduction of the zirconium concentration in structures of phosphates) a reduction of a specific surface of samples (from 10 to 1.3m2/g) and a progressive increase in surface acidity (from 5.2 to 14.7μmol/m2) are observed. Catalytic properties of the phosphates in reactions of methanol conversion in argon inert and air oxidative atmospheres were studied. Methanol dehydration to dimethyl ether is observed in inert atmosphere only and on the iron-free phosphate (y=0). Methanol dehydrogenation to formaldehyde takes place only in oxidative atmosphere, the degree of methanol conversion and formaldehyde selectivity depend on iron contents in the phosphate.

An universal method is presented for the synthesis of a wide range of aromatic acids via the reaction of carbonylation of appropriate halides under very mild conditions in the presence of cobalt carbonyl-based catalysts. The basic principles of a flexible manufacturing process for the manufacture of practically important acids and their derivatives were developed. The proposed process was successfully used for the utilization of the ecotoxicants polychlorobiphenyls used as dielectrics with a very high heat resistance.