Enhancement of CO2 capture in post combustion process using active carbon modified by amino acids

In this study, surface modification of a general purpose activated carbon is achieved through impregnation of three common amino acids namely, glycine, serine and lysine for CO₂ adsorption in post-combustion processes at temperature range 298–358 K. Glycine, due to its smaller molecular size, higher nitrogen content, and enhanced pore accessibility caused the adsorption to increase by 25% compared to original activated carbon uptake. Also, N₂ adsorption was evaluated to assess selectivity and competitive behavior. The modified adsorbents with glycine exhibited similar N₂ uptake to initial activated carbon at 358K. All adsorbents exhibited physisorption behavior, with ΔH _st values ranging from − 11 to − 33.9 kJ/mol for CO₂ and − 15.6 to − 17.8 kJ/mol for N ₂ . Overall, the results demonstrate that functionalizing by glycine, significantly enhances CO ₂ adsorption capacity of activated carbon. These findings provide valuable insights for designing tailored adsorbents for post combustion CO ₂ capture.