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Adsorption isotherms of carbon dioxide on the microporous ACC carbon adsorbent and the adsorption deformation of the adsorbent were measured. The heats of adsorption at tempera tures raising from 243 to 393 K and pressures from 1 to 5•10 6 Pa were measured. In the low temperature region (243 K), an increase in the amount adsorbed is accompanied by adsorbent contraction, and at high micropore fillings (а > 10 mmol g -1 ) the ACC carbon adsorbent expands. At high temperatures, adsorbent expansion is observed in the whole region of micropore filling. At 243 K in the low filling region (а < 1 mmol g -1 ), the heat of adsorption decreases smoothly from 27 to 24 kJ mol -1 . The heat of adsorption remains virtually unchanged in the interval 2 mmol g -1 < а < 11 mmol g -1 and then decreases to 8 kJ mol -1 at а = 12 mmol g -1 .Taking into account the nonideal character of the gas phase and adsorbent deformation the heats of adsorption are strongly temperature dependent in a region of high pressures.

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The relative adsorption deformaiion of several microporous carbon adsorbents was studied as a function of the benzene adsorption at relative pressure ranging from 1 9 10 -I to 1.0 and at 293 K. A correlation between the maximum compression of the sample and the characteristic energy of benzene adsorption of the Dubinin--Radushkevich equation was obtained. Using data on the adsorption deformation, it is possible to identify the region with a specific pore size that cannot be evaluated with the help of the Dubinin--Radushkevich equation.

The heat capacity of the H20/KNaX zeolite system has been measured at 34°C for various amounts of adsorption. The dependence of measured heat capacity of this system and calculated average molar heat capacity of adsorbate on the amount of adsorption passes through two distinct maxima. These maxima correspond to previously obtained waves in the plot of the heat of adsorption of water against the amount of adsorption for the same H20/KNaX zeolite system. The maxima are due mainly to the contribution to the heat capacity of the heat of transfer of a part of the water molecules from the adsorption sites with higher heat of adsorption to those with lower heat of adsorption. The thermal stability of different water associates in zeolite pores has been investigated. The differential heat capacities of adsorbed water were calculated and the changes in the heat of adsorption of water when the temperature of the system was increased were determined. The results show that with increasing temperature there is a smoothing out of the waves produced in the plot of the differential heat of adsorption as the function of the amount of water adsorbed.