Theoeretical study of the physical adsorption of aspirin on natural clinoptilolite

Abstract
The use of new formulations of antacid-aspirin have been studied in recent years. The natural zeolite clioptilolite–heulandite has been tested as an antacid and in the adsorption of aspirin. In this work we have performed a theoretical study of physical adsorption. The aspirin molecule was oriented to the cavities in three principal directions. The Coulomb potential for the different models was calculated in order to confirm the results obtained for the adsorption enthalpies. All the values obtained for the adsorption enthalpies were negative, which could explain the adsorption process of aspirin.