One-pot synthesis of self S-doped porous carbon for efficient CO2 adsorption

Abstract

Considering the rising environmental and efficiency concerns, the development of porous carbon via a surface decoration approach has received great attention for selectively adsorb CO2 from the flue gas. Herein, self-S-doped porous carbon was prepared from petroleum coke with high sulfur content (PHS) utilizing KOH as an activating agent. The effect of the activating temperatures and the KOH/PHS mass ratio on the physical feature and CO2 uptake performance of the as-synthesis porous carbons was fully examined. The optimal sample (PHS-650-3) presents the specific BET surface area and total pore volume of 1278 m2/g and 0.56 cm3/g, respectively. The PHS-650-3 sample displayed the maximum CO2 adsorption capacity of 4.18 and 5.57 mmol g−1 at 25 and 0 °C and 1 bar thanks to its enhanced textural characteristics and high amount of sulfur functionality on the surface. Last but not least, the as-synthesized S-doped porous carbon shows ideal adsorption solution theory (IAST) CO2/N2 selectivity of 21, fast adsorption kinetics, suitable heat of adsorption value and stable uptake capacity upon consecutive adsorption cycles, claiming its readily potential CO2 adsorption applications.