Bimodal Mesoporous Carbon-Coated MgO Nanoparticles for CO2 Capture at Moderate Temperature Conditions

Abstract

Bimodal mesoporous carbon supported MgO (MgOMC) materials were prepared to provide a candidate for trapping CO2 in flue gas at high temperature by an impregnation method. Textural properties of MgOMC were characterized by X-ray diffraction, N2 adsorption/desorption isotherm, scanning electron microscopy, transmission electron microscopy and an element mapping method, and their CO2 adsorption behaviors in both pure CO2 and 10 vol % CO2 simulated flue gas were evaluated by a thermal gravimetric method at ambient temperature. Effects of MgO content in composite and calcination temperature on CO2 adsorption capacity were studied. Results showed that MgOMC samples with high content of basic MgO sites and well-developed porous structure exhibit high CO2 uptakes at 75 °C, rapid adsorption kinetics, excellent CO2 selectivity in flue gas and good regenerability under mild temperature below 300 °C, indicating their potential application in the CO2 capture from flue gas.