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1. Gas chromatography was used to determine the thermodynamic characteristics of the adsorption of normal alkanes, normal alkenes, alkylaromatic, haloaromatic, and polyaromatic hydrocarbons on BaSO4, which is an ionic adsorbent, with a modified surface. 2. The retention of the molecules (except for normal alkanes) is significantly dependent on the specific interaction of the adsorbed molecules with the BaSO4 surface. 3. The contributions of the specific interaction energy to the heat of adsorption were evaluated.

1. The thermodynamic characteristics of the adsorption of ethers, ketones, alkyl acetates, normal alcohols, acetonitrile, nitromethane, dioxane, pyridine, and its methyl and dimethyl derivatives were determined by gas chromatography on an ionic barium sulfate adsorbent with modified surface. 2. The contributions from specific interactions to the total values of the differential changes in internal adsorption energy were determined for the given substances. 3. For certain isomeric compounds a direct relation was established between the retention and the dipole moment of their molecules.

1. A superthin multilayer fiber, Sivol, has significantly more developed porosity in comparison to the starting material, chrysotile asbestos. The values of S and the pore volume of Sivol are one order of magnitude higher than for chrysotile asbestos. 2. In contrast to Silokhrom, the adsorption values of CH3OH and H2O for Sivol and the silica fiber and the values of S calculated from the adsorption isotherms of these substances are significantly higher than the values measured with cyclo-C6H12 and krypton due to the specific interaction of the molecules of CH3OH and H2O with the surface of the adsorbents and the presence of fine pores in them.

1. When silicas are modified with amines, not all surface silanol groups participate in the chemical reaction. 2. When amine-modified silica gels are heated, water is produced; the maximum rate of the formation of gas occurs at 625 and 750 K. Destruction of the modifying layer begins with the liberation of ammonia at T > 640 K. 3. Adsorption of SO2 and CO2 on aminated silicas is determined by the surface concentration of amino groups, by their nature, and by their mutual position.

1. The adsorption of benzene vapor in the monomolecular surface filling range is much greater than the adsorption of n-hexane vapor on barium sulfate samples. The difference in adsorption increases as the baking temperature is raised and thus is not caused by hydration of the surface but by the ionic structure of the surface. 2. In contrast with hexane, when benzene is adsorbed on barium sulfate, interaction in addition to electrokinetic shows up principally between the surface electrostatic field and the π-electron bonds of the benzene molecule. 3. Comparing the adsorptions of benzene and n-hexane on various adsorbents shows that the effect of this additional interaction is determined by the chemical structure of the adsorbent surface layer.

1. The nitrogen adsorption in the monomolecular surface-filling range on barium sulfate samples baked at 400–500° is much greater than the argon adsorption. 2. In contrast with argon, when nitrogen is adsorbed on polar and ionic adsorbents there is, in addition to the electrokinetic and electrostatic induced interaction, an interaction between the electrostatic surface field and the adsorbed nitrogen molecules which have a large quadrupole moment.