Enhanced Cyclic CO2/N2 Separation Performance Stability on Chemically Modified N-doped Ordered Mesoporous Carbon

Abstract The modification of ordered mesoporous carbon (OMC) via NH3 heat treatment and subsequent amine refluxing at increased temperature was investigated to improve their performances for cyclic CO2/N2 separation stability and kinetics. Characterizations conducted with nitrogen adsorption/desorption isotherm, Fourier transform infrared spectroscopy, elemental analysis, and X-ray photoelectron spectroscopy demonstrated that the porosity and surface chemistry of the OMCs were tuned by modification. Adsorption evaluation with volumetric and gravimetric methods under various conditions indicated that the resulting amine-introduced N-doped OMC presented a high CO2 adsorption capacity with fast kinetics, outstanding selectivity at 50 °C and maintained superior separation performance after 20 cycles. The presence of accessible amino groups in considerable amounts renders the modified mesoporous carbon a promising candidate for CO2 capture from flue gas by using the temperature swing adsorption.