An experimental study of adsorption and variable temperature desorption of ethanol-water, propane-propylene and hydrogen sulfide-carbon dioxide-propane

An ideal adsorption only removes the desired components. Many times one or more other components are also adsorbed. If two or more components are adsorbed, an adsorption separation may not be satisfactory or may require additional separation procedures, even though one is highly preferentially adsorbed. In such cases it may be possible to get additional separation during the desorption stage by using variable temperature desorption. To study such problems, two experimental apparatus were set up, one for adsorption for ethanol and water mixtures on activated carbon and silicalite, the other for propane-propylene mixtures, and hydrogen sulfide-carbon dioxide-propane mixtures both on molecular sieves (SA and 13X). Both types of adsorption were followed by a stepwise desorption process with increasing temperatures. The study indicates that, in the desorption process the above three separations are significantly improved, with the more weakly adsorbed components being desorbed first at lower temperatures followed by desorption of the more strongly adsorbed components at higher temperatures. The method of variable temperature desorption may have useful applications in many adsorption separations --Abstract, page ii