Speaker
Description
The increasing concentration of carbon dioxide (CO₂) in the atmosphere is a major contributor to global climate change, creating a growing demand for efficient carbon capture technologies. Among the available separation methods, adsorption on solid porous materials has emerged as a promising alternative due to its high selectivity, low energy consumption, and operational simplicity. Synthetic zeolites, particularly 13X and 5A, are widely used for CO₂ capture because of their developed microporous structures and favorable adsorption properties.
Although zeolite-based adsorption has been extensively studied, a detailed understanding of the effects of operating conditions on adsorption kinetics is still required for process optimization. In particular, the influence of inlet CO₂ concentration, gas flow rate, and adsorbent type on breakthrough behavior remains of significant interest.
In this study, the adsorption kinetics of CO₂ on synthetic zeolites 13X and 5A were investigated using the breakthrough curve method. Experiments were performed in a fixed-bed adsorption column packed with 22.5 g of adsorbent at a bed height of 9 cm. A CO₂–air mixture was introduced under different operating conditions, with inlet CO₂ concentrations ranging from 5.2% to 15.6% and total flow rates from 14.67 to 21.83 L min⁻¹. Outlet CO₂ concentration and temperature were continuously monitored to determine breakthrough time, saturation time, adsorbed CO₂ mass, and temperature changes during adsorption.
The results showed that increasing the inlet CO₂ concentration and gas flow rate reduced breakthrough and saturation times while increasing the adsorbed CO₂ mass. The adsorption process was accompanied by a measurable temperature rise, confirming its exothermic nature. Zeolite 13X exhibited higher adsorption capacity at CO₂ concentrations around 10%, whereas zeolite 5A showed better performance at lower CO₂ concentrations (~5%). These findings provide useful insights for the optimization of adsorption-based CO₂ capture systems.
Keywords: CO₂ adsorption, zeolites, breakthrough curves, adsorption kinetics, fixed-bed column.