THERMAL ASPECTS OF GAS-ADSORPTION PROCESS ES

The adsorption of gases is an exothermal phenomenon, and fixed bed ads orption operations produce high thermal effects. Similarly, applying t emperature changes to a process can modify adsorption. The purpose of this paper is to illustrate the basic features of non-isothermal adsor ption, the most salient of which is the effect of relative velocities of heat and concentration waves. It is shown that there may exist a te mperature at which a reversal occurs in the order of those velocities. A simple purification process is suggested, based on the temperature modulation of the gas mixture fed to the column. Examples are calculat ed with data corresponding to carbon dioxide adsorption on 13X molecul ar sieves.