High-Pressure CO2 Adsorption onto NaX Zeolite: Effect of Li^+ , K^+ , Mg^2+, and Zn^2+ and Equilibrium Isotherms Study

Due to the adverse effects of Carbon dioxide (CO2) emissions on the environment; various mitigation is regulated to control its emissions. In this study, CO2 adsorption isotherms on NaX or Faujasite X and exchanged zeolites with Li^+ (LiX), Zn ^+ (ZnX), Mg^2+ (MgX) and K^+ (KX) at different temperatures (298, 308, 323, 353, and 362 K) were investigated, using high pressure (3 MPa (30 bar)) thermogravimetric analyzer. The experimental results were then validated using numerous isotherm kinetics models namely Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Elovich, Toth, and Sips. From the study, it was found that the CO2 adsorption isotherms are characterized by a strong increase in low-pressure adsorption and a trend towards a high-pressure limit value Qmax. Specific surface area and pore volume revealed the most significant influent parameters for this study. These findings revealed that both experimental and modeling well correlated with Toth and Sips, gave the best results regardless of the material used.