https://doi.org/10.1016/j.fuel.2022.123953
“On the other hand, it is also noticeable that all zeolites display isotherm profiles, which are typical of microporous materials, namely, the quantity of CO2 adsorbed increases abruptly with the increase on the equilibrium pressure in the low-pressure range, and smoothly at higher pressures. This type of isotherm is related to type-I isotherm according to International Unit Pure and Applied Chemistry (IUPAC) classification [42] and is characteristic of adsorption in monolayer. In fact, it can be observed a clear relation between of the CO2 adsorption capacity and the micropore volume since those adsorbents with higher CO2 uptake are also those materials with higher microporosity (Fig. 6A).”
“Fig. 6. Relationship between the CO2 adsorption capacity (at 25 °C and 1 bar) and (A) microporosity of the adsorbents and (B) b-parameter estimated by the Toth equation.”
“The CO2 adsorption isotherms for the synthesized zeolites and commercial 4A zeolite were well fitted to Toth equilibrium equation. This adsorption model assumes that the adsorption exclusively takes place with sub-monolayer coverage.”