| Abstract
| - Characteristics of porous structure of silica gel Si-60 (pristine and covered by different amounts ofpyrocarbon prepared by pyrolysis of acenaphthene, acetylacetone, and glucose, then heated at 500 °C inair or hydrothermally treated (HTT) at 150 or 200 °C, and also heated at 500 °C) were analyzed by usingTEM, 1H NMR, and adsorption−desorption of nitrogen at 77.35 K. The structural parameters were estimatedby the direct minimization method or the overall isotherm approximation with a regularization procedure.Pyrolysis of different organics on Si-60 is accompanied by marked changes in the pore structure dependingon the nature of precursors. Hydrothermal treatment of silica gel and carbosils at 150−200 °C for 6 hresults in a strong modification of both pores and outer surfaces of silica gel particles in contrast to heatingof pristine Si-60 or carbosils (after HTT) at 500 °C in air for 24 h. Computations of the distributions ofthe pore size and nitrogen adsorption energy, as well as 1H NMR spectra of the interfacial water, revealan increase in the adsorbent nonuniformity due to hydrothermal treatment, but heating of silica gel andpyrocarbon/silica in air gives the opposite result.
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