ABSTRACT
I. ADSORPTION AND DESORPTION IN MICROPOROUS MEDIA
A. Microporous Adsorbent from the Synthesis to the Uses
Most existing processes for synthesis of microporous adsorbents comprise, as the final stage, a treatment of the obtained porous materials under high temperatures. When the synthesis is achieved, the fresh micropores are not empty but contain some gas or vaporgas mixture consisting of volatile components delivered from the solid phase during the synthesis and/or products of their oxidation. When the adsorbent is cooled, the micropores adsorb also the gas from the environment (probably air):
Ads+G→Ads·G (4.1)
When the adsorbent is, after all, in contact with the gas, adsorption of which is needed, the interaction between the gas and the adsorbent consists not in the entering of the gas into voids inside the adsorbent but in the replacement of the previously adsorbed volatile components with the new adsorbate:
Ads−G+G*→Ads·G*+G (4.2)
The kinetics of reaction (4.2) is given by the following equation:
(4.3)
where k+GG* and k−GG* are constants of the rate of the direct and the reverse reactions (4.2), Ci is the concentration of ith component in the solid phase, and Pj is the partial pressure of jth volatile component in the gaseous phase.
