Isosteric and Differential Heats of Adsorption

Adsorption is a general tendency of matter and during its occurrence, a decrease in the surface tension is experienced by the solid. For this reason, adsorption is a spontaneous process, where a 

The Physical Chemistry of Materials Energy and Environmental Applications 

Accordingly, adsorption is an exothermic process, and thereafter the a process favored by a decrease in temperature. 

U is the internal energy of the system S is the entropy V is the volume T is the temperature p are the chemical potentials 

The thermodynamic approach applied here considers the adsorbent plus the adsorbed gas, or vapor, as a solid solution (system aA). Applying this description, it is feasible to get the fundamental thermodynamic equation for the aA system [2,15,16,25] 

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