Abstract
MgO/MCM-41 materials with weak basic sites were synthesized by dispersing MgO onto mesoporous Si-MCM-41. Such MgO-modified MCM-41 materials were characterized by Fourier-transform infrared spectroscopy (FT-IR), temperature programmed desorption (TPD), X-ray diffraction (XRD) and N2 adsorption/desorption measurements. The results indicated that the surface area, pore size and pore volume of the materials decreased with the introduction of MgO. Their CO2 uptakes could be significantly improved when the MgO loading was increased from 0 wt% to 20 wt%. CO2-TPD and in situ FT-IR measurements showed that the materials possessed weak basic sites which could react with CO2 to form bicarbonate species and thereby improve the CO2 uptake. As a result, the adsorbed CO2 could be desorbed completely from the sample at 200 °C. In addition, the MgO/MCM-41 materials had a high thermal stability and showed promising performances in practical applications.
