Experimental Adsorption and Modelisation of CO 2 on Adsorbents Collected from Elborma Field in South Tunisia

Abstract

In order to select the best adsorbant for CO2 sequestration, this study deals the interaction be-tween clay, Triassic sandstone and Jurassic evaporate and CO2. These materials have been used as sorbents. To choose the adequate geological layers for sequestration and with minimum risk of leakage, adsorbent characterizations were investigated using X-ray diffraction, SEM and surface area analysis, structural and textural shapes of these materials have been investigated too. The elution chromatography in gaseous phase has been employed to determine the adsorption iso-therms of adsorbed CO2 for each adsorbent. Then, the treatment of the experimental data allowed us to compare each CO2/adsorbent couple. The adsorption isotherms were modeled using the Langmir and Freundlich models. A thermodynamic comparison between the different adsorbents will also be provided. Experimental results show that clay and Triassic sandstone have the highest rate of adsorption amount. It has been also found that the Langmuir model is the most appropriate one to describe the phenomenon of CO2 adsorption on clay. However, for the other adsorbents (i.e. Triassic sandstone and Jurassic evaporates) the two-models are adequate.