Concentration of carbon dioxide (CO2), a major greenhouse gas, is continuously increasing, leading to global temperature rise. Carbon Capture and Storage (CCS) technology has gathered attention as a solution to this issue. CO2 capture stage accounts for a significant portion of the overall cost of the CCS process, making improvement of capture technology efficiency crucial for cost reduction. CO2 adsorption process using solid adsorbents is actively researched due to its relatively easy regeneration and high capture efficiency. Among various adsorbents, hydrotalcite is a solid adsorbent applicable for medium-temperature CO2 adsorption, suitable for industrial environments where exhaust gases are emitted at 200-400 ℃. However, its adsorption performance is lower compared to other high-temperature adsorbents, prompting research to enhance its performance. This study introduces alkali metal salts into hydrotalcite-based CO2 adsorbents to optimize their ratios for improved CO2 adsorption at medium temperatures. Hydrotalcites containing different alkali metal salts were synthesized using the hydrothermal method. Their adsorption performance was then correlated with the characteristics of the adsorbents through detailed characterization.
