CO2 adsorption on carbon molecular sieves

The effect of the textural properties of a series of commercial carbon molecular sieves (CMS), prepared from different polymeric precursors, on their ability for CO2 adsorption at different temperatures has been studied. The adsorbents have been characterized by N2 and CO2 adsorption at 77 and 273 K, respectively, together with measurements of immersion calorimetry into liquids of different molecular dimensions. The studied CMSs cover a wide range of porosity, from purely microporous carbons to samples containing wide micropores as well as a certain proportion of mesoporosity. Studies of CO2 adsorption, at atmospheric pressure (1 bar) and three different temperatures (273, 298 and 323 K), have shown that a high CO2 adsorption capacity requires the presence of a well-developed microporosity, as well as a high volume of narrow micropores. On the other hand, narrow micropores seem to be the key factor leading to a maximum capacity of CO2 adsorption, even at temperatures close to that of anthropogenic emissions of CO2.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► CMS have been fully characterized by adsorption and immersion calorimetry. ► High CO2 adsorption capacity requires a well developed microporosity. ► Narrow micropores are the key factor leading to high CO2 adsorption capacity.