CO₂ Adsorption on Biomass-Derived Carbons from Albizia procera Leaves: Effects of Synthesis Strategies

CO₂ capture is a useful strategy for controlling the risks associated with global warming. The design of an adsorbent is essential for clean and potentially energy-efficient adsorption-based carbon capture processes. This study reports a facile and moderately temperature single-stage combined pyrolysis and activation strategy for the synthesis of nitrogen-doped carbons for high-performance CO₂ capture. Using nitrogen-rich Albizia procera leaves as the precursor and carrying out single-stage pyrolysis and activation at temperatures of 500, 600, and 700 °C in the presence NaHCO₃ as an activating agent, carbons with different surface characteristics and ultrahigh weight percentage (22-25%) of nitrogen were obtained. The subtle differences in surface characteristics and nitrogen content had a bearing on the CO₂ adsorption performance of the resultant adsorbents. Outstanding results were achieved, with a CO₂ adsorption capacity of up to 2.5 mmol/g and a CO₂ over N₂ selectivities reaching 54. The isotherm results were utilized to determine the performance indicators for a practical vacuum swing adsorption process. This study provides a practical strategy for the efficient synthesis of nitrogen-doped carbons for various adsorption applications.