Investigation and Development of Protective Ointments III*

Abstract

The adsorption of sarin from n-heptane solutions by silica gels, alumina, bentonite, and certain carbonaceous adsorbents was studied. The results obtained have been interpreted according to the Langmuir adsorption isotherm. Of the various adsorbents tested, those of a silicaceous nature were found to be superior, exhibiting very strong adsorptive tendencies toward the fluorophosphate ester. A linear relationship was found to exist between the limiting adsorptive capacity and the specific surface area of the adsorbents. The average area occupied by a sarin molecule, furthermore, was found to be approximately 80 Ų, irrespective of the adsorbent, a value in reasonable agreement with that suggested by a molecular model. Both of these relationships indicate that sarin is adsorbed primarily as a unimolecular layer.