A porous activated carbon was synthesized from sawdust through carbonization at temperatures between 700–1100 °C followed by activation with CO₂. The resulting activated carbon exhibited a hierarchical and microporous structure with a surface area of 1651.34 m²/g, pore volume of 0.69 cm³/g, and pore size of <1.76 nm. It demonstrated a CO₂ adsorption capacity of 9.2 mmol/g at 25 °C and 1 bar, and a CO₂/N₂ selectivity of 40.2. The material showed excellent recyclability over 10 cycles, indicating its practical application for CO₂ capture. The study highlights the potential of this activated carbon as an efficient and selective material for CO₂ capture, contributing to efforts to mitigate anthropogenic CO₂ emissions. The synthesis method is low-cost and sustainable, utilizing abundant and inexpensive raw materials. The activated carbon's high surface area and hierarchical pore structure enable effective CO₂ adsorption and separation, making it a promising candidate for industrial and environmental applications. The results demonstrate the effectiveness of the activation process in enhancing CO₂ capture performance, with the optimal carbonization temperature of 1000 °C yielding the highest CO₂ uptake and selectivity. The material's recyclability and selectivity make it a viable option for large-scale CO₂ capture applications.A porous activated carbon was synthesized from sawdust through carbonization at temperatures between 700–1100 °C followed by activation with CO₂. The resulting activated carbon exhibited a hierarchical and microporous structure with a surface area of 1651.34 m²/g, pore volume of 0.69 cm³/g, and pore size of <1.76 nm. It demonstrated a CO₂ adsorption capacity of 9.2 mmol/g at 25 °C and 1 bar, and a CO₂/N₂ selectivity of 40.2. The material showed excellent recyclability over 10 cycles, indicating its practical application for CO₂ capture. The study highlights the potential of this activated carbon as an efficient and selective material for CO₂ capture, contributing to efforts to mitigate anthropogenic CO₂ emissions. The synthesis method is low-cost and sustainable, utilizing abundant and inexpensive raw materials. The activated carbon's high surface area and hierarchical pore structure enable effective CO₂ adsorption and separation, making it a promising candidate for industrial and environmental applications. The results demonstrate the effectiveness of the activation process in enhancing CO₂ capture performance, with the optimal carbonization temperature of 1000 °C yielding the highest CO₂ uptake and selectivity. The material's recyclability and selectivity make it a viable option for large-scale CO₂ capture applications.