Synthesizing MgO with a high specific surface for carbon dioxide adsorption

Abstract

In this work, highly porous MgO was synthesized for CO₂ adsorption by a simple and economic thermal decomposition of basic magnesium carbonate and magnesium oxalate. Characterizations of the synthesized samples were accomplished using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and nitrogen adsorption–desorption isotherms. The results showed that the synthesized MgO possessed a high BET surface area in a range of 161–252 m² g⁻¹ and a highly porous structure. Thermo gravimetric analysis revealed that the synthesized MgO not only showed good selectivity to CO₂ but also yielded a CO₂ adsorption capacity of as high as 7.59 wt%. Besides, in situ FTIR spectroscopy and CO₂ TPD curves demonstrated that the adsorption mechanism of synthesized MgO was mainly attributable to chemisorption and it could be regenerated at relatively low temperature. This work provides a new way to synthesize MgO with a highly porous structure for CO₂ adsorption.