Influence of pyrolytic coke deposition on silica gel structure.

Commercial silica gel, type Si-60, was coated by pyrolytic coke during diff erent times. The porous structure of obtained carbon-silica adsorbents (car bosils) was analysed on the basis of nitrogen adsorption-desorption measure ments at 77,5 K. The equation of Dubinin and Izotova and the Horvath-Kawazo e adsorption model were used for determining the micropore structural param eters. The fractal analysis was performed on the basis of the Frenkel, Hals ey and Hill theory and analysis of adsorption data. The new correlation bet ween fractal dimension and average pore size associated with the power law was found. The fractility factor, defined as a measure of a distance from a completely smooth surface, was used for analysis in influence of fractalit y on the changes of porous structure.