Solidothermal synthesis of nitrogen-decorated, ordered mesoporous carbons with large surface areas for efficient selective capture and separation of SO2

Abstract

As a typical corrosive and toxic exhaust gas, the effective elimination of sulfur dioxide is of great importance for flue gas desulfurization. Yet the facile synthesis of adsorbents with high capture capacity (especially at low partial pressures) as well as excellent stability remains a challenge. Herein, we reported the preparation of N-functionalized ordered mesoporous carbons through a solvent-free self-assembly strategy for selective capture and separation of SO2 via enhanced base-acid host–guest interaction. The N-doped ordered mesoporous carbons were synthesized using Pluronic F127, terephthalaldehyde, and m-aminophenol as raw materials, then followed by activation with KOH. The synthesized N-OMC-T samples are found to exhibit large specific surface areas (∼1191 m2/g) and multifunctional nitrogen base sites. The synthesized K-N-OMC-T samples show excellent SO2 capacity with 13.15 mmol/g at 1.0 bar and 25 °C, and the corresponding IAST selectivities for SO2/N2 and SO2/CO2 reach up to 195.8 and 16.4 (25 °C), respectively. The breakthrough tests further demonstrate the impressive elimination of SO2 from SO2/CO2/N2 gas mixture by K-N-OMC-T samples. Thus, it is believed that the possibility for selective SO2 capture from flue gas is for K-N-OMC-T samples.