Gas/adsorbent interaction dynamics: an experimental approach

A procedure for the study of gas/adsorbent dynamics is presented. As an example, the interaction between CO₂/He with trace amount of CF₄ and alumina was studied under low-level CO₂ concentrations. Gas chromatography coupled with a thermal conductivity detector was utilized for assessing the temporal variation of the compound concentrations. The chromatographic technique allowed to follow the CO₂ and CF₄ concentrations with a precision of 15 ppm, and 1 ppm, respectively. Up to CO₂ contents of 10⁴ ppm_v, the results showed that the interactional dynamics is controlled by the magnitude of the initial concentration. The sorption capacity of alumina was found to be low, not exceeding 0.5% g [CO₂]/g alumina. Considerations based on the material properties were made explicit in order to explain the preferential CO₂ adsorption by alumina