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The physicochemical properties of nanoporous carbon materials (TUMaNs) prepared by the carbonization of porous phenol-formaldehyde resin were studied. According to high-resolution electron microscopic data, these materials are nanographites composed of 5-to 10-μm globules, which form chaotically arranged microblocks 3–4 graphene layers in thickness. The materials have a developed system of 1.5-to 3.0-nm micropores and a specific surface area of 450–700 m2/g. According to X-ray diffraction analysis, the samples consisted of strongly disordered graphite with uniquely large interlayer distances of 0.375–0.390 nm. The sorption properties of TUMaN toward hydrogen and light hydrocarbons were studied. The amount of absorbed hydrogen was higher than analogous values for materials with comparable or even larger specific surface areas. With respect to the sorption of light hydrocarbons, the properties of TUMaN were similar to those of silica and alumina. Nickel supported on TUMaN exhibited an unusually high activity and selectivity in butadiene hydrogenation to butenes. Palladium on TUMaN was highly effective in the hydrofining of ethylene for the removal of acetylene impurities.

Evaporation of metallic silver was performed in Ar, N 2 and He using the ELV-6 electron accelerator. The obtained ultra-dispersed powders with a particle size of 70–80 nm were investigated by XRD, HREM and UV–Vis spectroscopy. The structure of Ag(Ar) powder was shown to differ substantially from that of Ag(N 2 ) by the presence of small oxide-like species of 10–20 nm on the particle surface. Catalytic activity of the powders in the reaction of ethylene epoxidation was also studied.

The syntheses of triisopropyl borate and other boric acid esters under conditions of mechanochemical activation with the use of zeolite catalysts were found to be highly efficient. The proposed method exhibits the following advantages over known methods: short synthesis times, low energy consumption, higher yields of target products, and the absence of byproducts. The mechanism of the catalytic esterification of boric acid under conditions of mechanochemical activation is discussed.

Two carbon material — sibunit and altunit have been studied using X-ray phase analysis methods. Coherent scattering region of Sibunit is a globule with a diameter of 35 A, which preserves a stratified structure of graphite with the azimutal disorientation of graphite networks. Altunit has a diamond structure and consists of small particles with the average size of 20 A, having no microstrains and characterized by a narrow size distribution of particles.

Regularities for adsorption of HAuCl4, H2PdCl4 and H2PtCl6 on carbon supports as a stage of preparation of supported metal catalysts have been studied. The results obtained have been interpreted in terms of the electrochemical theory of adsorption of electrolytes. Relationship between the nature of adsorption of these precursors and the metal state in the target catalysts has been revealed.

Catalysts based on Rh(III) complexes with amine polymers PEI and AN-221 are shown to be active and stable catalysts for dihydrogen evolution from water by such strong one-electron reductants as V 2+ (aq) and Cr 2+ (aq) . For granular Rh—AN-221 at high ( > 5 × 10 −3 M) V 2+ concentration, the rate of hydrogen evolution was found to be determined by diffusion of the reaction products, i.e. V 3+ cations and/or hydrogen molecules, inside the polymeric granules. The highest specific catalytic activity registered for the polymeric catalysts equals 640 mol H 2 (g-atom Rh) −1 h −1 for Rh—AN-221. The active component of the rhodium-polymeric catalysts was proved by a number of physical methods to be highly dispersed metallic rhodium particles chemically bound to the polymer. The electronic properties of rhodium differ somewhat from those of bulk metal due to a strong interaction between the rhodium particles and the polymeric support.

IR spectroscopy, ESCA and RAD studies indicate that in contrast to, impregnation catalysts, platinum and lead in the anchored, reduced (Pb+Pt)/SiO2 catalysts interact, thus decreasing the electron density on Pt.

The structure of sulphided W/SiO2 and (Ni,W)/SiO2 catalysts prepared by various techniques was studied by means of an X-ray method (radial electron distribution technique).In all catalysts after treatment with H2S at 400° the formation of surface species with the structure of WS2 sheet was observed. No distances typical of nickel sulphides but distances between atoms of two neighbouring WS2 sheets have been detected. Geometrical compatibility of the structure of WS2 sheet and that of surface layer SiO2 is considered.

X-ray and structural characteristics of iridium and platinum blacks of various dispersity in the coherent scattering region from 40 to 700 A have been studied. High dispersity blacks are shown to contain crystalline and X-ray amorphous particles with a disordered structure and decreased coordination number. For such blacks a 0.003 A increase in the unit cell parameter is observed.

Structure and adsorption properties of new carbon carriers obtained on the basis of carbon black have been examined. These carriers possess largely mesoporous structure, developed surface and high mechanical strength and contain hollow globules. Walls of these globules have pores, whose size is several hundreds A. The new material is of interest for fundamental studies of carbon-supported catalysts.

1. By the use of NaBH4 it is possible to reduce individual nickel cations, in zeolites and on silica gel, at temperatures below room value. 2. The fact that the boron-containing metal resulting from such reduction is highly active in olefin hydrogenation is due, in part, to the high degree of disperson of the metal and, in part, to the participation of the reactive B-H bonds in the hydrogenation process. 3. The fact that the boron-containing metal shows low catalytic activity in the hydrogenation of benzene may be due to retention of an electron-deficient state by the metal particles in the reaction mixture.