A review of biomass porous carbon for carbon dioxide adsorption from flue gas: Physicochemical properties and performance

Carbon capture is widely recognized as an effective method for reducing CO2 concentrations in the atmosphere. Solid material adsorbents offer advantages in terms of energy-efficient, environmental-friendliness, and low-cost, and thus hold significant potential in CO2 capture. Biomass porous carbon exhibits advantages including a large specific surface area, rich pore structure, adjustable surface chemistry, high hydrophobicity, and good cycling stability. However, less favorable CO2 adsorption capacity and selectivity at low partial pressures limit its application. This paper investigates the CO2 adsorption mechanisms of biomass porous carbon at the microscopic level, elucidating the contributions of micropores, mesopores, and macropores, as well as the important roles of heteroatom and amine functional groups in enhancing CO2 adsorption capacity and selectivity. Furthermore, a comprehensive review is provided on methods to enrich micropore volume, construct hierarchical porous structures, and modify chemical functional groups, summarizing the characteristics and future development of each approach. Finally, by analyzing the CO2 adsorption performance data of biomass porous carbon, the feasibility of its industrial applications is discussed, including its suitability in Temperature Swing Adsorption (TSA) and Pressure Swing Adsorption (PSA) processes. Further research is needed to deepen our understanding of the CO2 adsorption of biomass porous carbon, with future studies focusing on the relationship between the synergistic effects of physical structure and chemical functional groups. The findings of this study provide guidance for the development of biomass porous carbon as a green, efficient, stable, and commercially viable adsorbent, with potential applications in post-combustion CO2 capture such as in coal-fired power plants.