Experimental Studies and Equilibrium Modeling on the Adsorption of CO ₂ by ZSM‐5 Zeolite and Activated Carbon

ABSTRACT The objective of our paper is to compare the CO 2 adsorption and the kinetic studies of ZSM‐5 zeolite and activated carbon (AC). Both adsorbents were described with N 2 adsorption–desorption isotherm, scanning electron microscopy (SEM), and X‐ray diffraction (XRD). The CO 2 adsorption isotherms were collected at different temperatures over a wide range of pressures and modeled with the Langmuir and Freundlich models. The characterization results showed that AC exhibited larger total pore volume, higher BET surface area, and higher crystallinity in comparison with the ZSM‐5 zeolite. The results showed that the quantities of CO 2 adsorbed on the AC were greater than on ZSM‐5, since AC exhibits more important textural parameters than zeolite. Furthermore, the Langmuir model provides the perfect adjustment to the experiments, with a correlation coefficient ( R 2 ) of 0.99. The CO 2 adsorption kinetics can be depicted by the linear driving force (LDF) model. With rising temperature, the mass transfer constants of CO 2 adsorption on the two adsorbents rise. With increasing pressure, the adsorption activation energy Ea for CO 2 on both adsorbents is reduced. Moreover, the of AC was higher than that of zeolite ZSM‐5 at low pressure. The findings can be integrated into the adsorption system for removing CO 2 from the gases.