A direct synthesis of mesoporous carbon supported MgO sorbent for CO2 capture

Ordered mesoporous carbon supported MgO (Mg-OMC) materials were synthesized by the carbonization of sulfuric-acid-treated silica/triblock copolymer/sucrose/Mg(NO3)2 composites. In the current approach, triblock copolymer P123 and sucrose were employed as both structure-directing agents for the self-assembly of rice husk ash silica solution and carbon precursor. Sulfuric acid was used to cross-link P123 and sucrose in the as-synthesized composites in order to improve the carbon yield. The synthesized Mg-OMC was characterized by X-ray diffraction, N2 adsorption–desorption isotherm method, X-ray photoelectron spectroscopy, scanning electron microscope equipped with energy dispersive X-ray analysis and transmission electron microscopy. The thermal stability of Mg-OMC was verified by CO2-temperature programmed desorption, which confirmed the chemisorption of CO2 on MgO. The CO2 adsorption capacity of Mg-OMC-1 was observed to be 92 mg/g of sorbent which is comparable with that of the well established CO2 sorbents.