Facile Synthesis of MgO-Modified Carbon Adsorbents with Microwave- Assisted Methods: Effect of MgO Particles and Porosities on CO(2) Capture

In this study, magnesium oxide (MgO)-modified carbon adsorbents were fabricated using a nitrogen-enriched carbon precursor by microwave-assisted irradiation for CO(2) capture. The X-ray diffraction (XRD) patterns showed the characteristic diffraction peaks of MgO at 43° and 62.5°, and no impurities were apparent. By changing the microwave reaction time, the spherical structure of the parent material was transformed to a hybrid structure with MgO crystalline particles in a carbon matrix. The morphology evolution and properties of the prepared materials were also investigated using transmission electron microscopy and N(2) adsorption, respectively. On optimising the conditions, the prepared sample attained a high CO(2) uptake of 1.22 mmol/g (5.3 wt.%) under flue gas conditions (15% CO(2) in N(2)). It was found that MgO affected the CO(2) capture behaviour by enhancing the fundamental characteristics of the carbon surfaces.