Ordered mesoporous carbon with enhanced porosity to support organic amines: efficient nanocomposites for the selective capture of CO2

Abstract

Organic amine impregnated porous materials have been widely used in carbon dioxide (CO₂) capture, because they possess large CO₂ capacities and good selectivity, and can be easily recycled. In this paper, activated ordered mesoporous carbon (AOMC) with an extremely large Brunauer, Emmett and Teller surface area (2903 m² g⁻¹) and pore volume (3.40 cm³ g⁻¹) is reported, which was directly synthesized from the activation of ordered mesoporous carbon (OMC) using sodium amide. Because of the significantly expanded nanoporosity and highly ordered mesopores, the synthesized AOMC could accommodate much more poly(ethyleneimine) (PEI) than the pristine OMC (60.2 wt% versus 28.5 wt%). The resultant PEI@AOMC shows a much enhanced adsorption capacity (2.58 and 1.84 mmol g⁻¹, at 30 °C and 75 °C) for CO₂ in comparison with the pristine AOMC (1.61 and 0.72 mmol g⁻¹, at 30 °C and 75 °C). Therefore, the PEI@AOMC composites will find important applications for the selective adsorption of CO₂ in various industrial processes.