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UDC 544.723.21 N. D. Lysenko, V. G. Il'in, and P. S. YaremovMicro-mesoporous materials combining the structural and sorption characteristics of a mesoporous molecular sieve (MMS) and zeolite BEA were obtained by the "dry gel conversion" method -partial zeolitization of silica MMS SBA-15 in the presence of tetraethylammonium hydroxide. The volume of the mesopores reaches 0.65 cm 3 /g, while that of the micropores is in the region of 0.1 cm 3 /g. The acidity of the obtained zeolitized materials differs from that of BEA; the total concentration of medium-strength acid centers (maximum thermal desorption of ammonia at~315°C) amounts to 0.15 mmol/g.Distinctive features of mesoporous molecular sieves (MMS) of the MCM-41, MCM-48, SBA-15, and SBA-16 types and their analogs are their spatial ordering, structural periodicity in the nanometer range of distances, uniform porosity (pore diameters from 2 to 10 nm or more, volumes of about 1 cm 3 /g), and developed surface area (up to 1200 m 2 /g) [1][2][3]. This would seem to make them extremely attractive as subjects for the investigation of adsorption processes and promising in respect of practical applications (adsorbents, ion exchangers, catalyst supports, photocatalysts, sensing elements, etc.). However, as a result of the amorphous state and the critically low degree of condensation (at a level of 50%) of the framework-forming substance siliceous MMSs have relatively low hydrolytic stability. Moreover, in spite of the significant porosity and the developed surface area aluminosilicate MMSs have acid centers with low concentrations and strengths compared with zeolites (Zt). It is also necessary to note the marked complexity of synthesis for ordered AlSi-MMSs with high Al contents as a consequence of destruction of the template micellar structures resulting from interaction of the compensating alkyltrimethylammonium cations with the anionic centers (AlO 4/2 )in the alkaline medium and the high solubility (and, accordingly, the reduced inclusion of Al in the framework) during synthesis in acidic reaction media (RM).An alternative to aluminosilicate mesoporous molecular sieves (AlSi-MMS) as the basis of catalysts may be provided by materials that combine the properties of the MMS (an open and penetrable sorption space) and the zeolite (crystallinity, microporosity, active adsorption, ion-exchange, and catalytic centers). Two main approaches to the formation of such hybrid and/or composite materials are possible. One involves the use of nanoparticles of the initial precursor sol of the Zt as starting material for the subsequent "assembly" and formation of the MMS structure in the presence of an appropriate structure-directing agent (a micellar template) [4][5][6][7]. The other approach presupposes partial zeolitization of the MMS in the so-called "dry gel conversion" process after preliminary impregnation with an aqueous solution of the organic template, which is required for the nucleation and formation of the crystallites of the Zt phase [5,[8][9][10].

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UDC 544.723.21 N. D. Lysenko, M. V. Opanasenko, P. S. Yaremov, A. V. Shvets, and V. G. Il'inWe have carried out a comparative study of matrix carbonization of some organic precursors (sucrose, polydivinylbenzene, polyphenol-formaldehyde, polyacrylonitrile, acetonitrile) in SBA-15 and KIT-6 silica mesoporous molecular sieves. We have shown that carbon mesoporous molecular sieves of the CMK-8 type, obtained in KIT-6 mesopores, have better adsorption characteristics due to the features of the three-dimensional cubic structure, the larger pore volume and thickness of the walls of the framework. The maximum micropore volume is observed in CMK-3 and CMK-8, obtained by carbonization of polyphenol-formaldehyde and polydivinylbenzene, while the greatest specific surface area is observed on carbonization of sucrose, where the maximum hydrogen adsorption capacity is achieved at a level of 1.4 wt.% (77 K, 1 atm). We show that the mesopore surface coverage by hydrogen in carbon mesoporous molecular sieves increases as the degree of graphitization increases.Porous carbon materials are widely used in sorption processes for water and air purification, separation of gases, in chromatography, catalysis, etc.[1]. This is because of their properties, in particular their extended surface area, large pore volume, chemical inertness, and high mechanical stability. Carbon microporous and mesoporous materials [2] generally are obtained by carbonization of carbon-containing substances of natural or synthetic origin, followed by activation of the samples. One of the most promising methods for obtaining microporous and mesoporous carbon materials is the matrix synthesis method [3][4][5], which essentially involves subjecting an organic precursor to carbonization in the pores of an inorganic mesoporous matrix (in particular, a silica matrix), the carbon formed as a result of pyrolysis is separated by treatment of the carbon-silica composite with hydrofluoric acid or a base. The matrix carbonization method makes it possible to control the porosity of the carbon material by varying the structure, composition, and size of the pores in the original matrix (the exotemplate), the nature of the organic precursor, and the coverage of the matrix pores by it, the pyrolysis conditions, etc.The aim of this work was to determine the characteristic features of matrix carbonization of different types of organic precursors (sucrose (s), polyacrylonitrile (pAN), polydivinylbenzene (pDVB), polyphenol-formaldehyde (pFF), acetonitrile (ac)) in silica mesoporous molecular sieves (Si-MMS), and also the associated features of the porous structure and adsorption properties of the carbon mesoporous molecular sieves (C-MMS) obtained.