Adsorption-absorption technique for effective CO₂ capture

This paper presents a study on the removal of CO₂ gas from gas mixture (CO₂/N₂) of 14% CO₂ using adsorption onto zeolite 13X in a fluidized bed at 298 K and 1 atm pressure. The effects of static bed height (5–25 cm) and rate of flow of the gas mixture (6–14 L/min) on the breakthrough time were studied. The desorption of CO₂ was performed by absorbing the adsorbed CO₂ molecules using NaOH solution (0.1 M). The absorption process which was accompanied with chemical reaction achieved two objectives. The first was converting CO₂ gas into a valuable substance (Na₂CO₃) which could be used in many industries. The second was the storage of CO₂ gas in what was called a chemical carrier which could emit the gas when it was needed. The effect of static bed height (5–25 cm) on the absorption process in the fluidized bed was also studied. For the adsorption process, the results showed that the breakthrough time increased with decreasing the flow rate but with increasing the static bed height. In the desorption process, the total amount of absorbed CO₂ molecules was 396 mg, achieving a recovery of 90.8% at 5 cm static bed height. Studying the adsorption in a fluidized bed.Using breakthrough curve to estimate the adsorbed amount of CO₂.Studying the effects of operational parameters on the breakthrough time.Performing the desorption by absorption process.Recovering the adsorbed CO₂ molecules. Studying the adsorption in a fluidized bed. Using breakthrough curve to estimate the adsorbed amount of CO₂. Studying the effects of operational parameters on the breakthrough time. Performing the desorption by absorption process. Recovering the adsorbed CO₂ molecules.