Preparation and characterization of PEI-loaded MCM-41 for CO2 capture

MCM-41, a molecular sieve, was prepared using tetraethoxysilane and cetyltrimethylammonium bromide and used as an effective adsorbent for CO₂. By using the wet impregnation method, various weights of poly(ethyleneimine) (PEI) were modified on mesoporous silicate MCM-41 for increasing the CO₂-adsorption capacity. The samples were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and nitrogen adsorption/desorption isotherms. Thermal gravimetric analysis (TGA) was conducted to investigate the CO₂ capture behaviors. PEI was successfully dispersed into the channels of MCM-41, shifting the (110) diffraction peaks in the XRD patterns. The specific surface area and total pore volume of the PEI-loaded MCM-41 adsorbent decreased when the weight of PEI loading increased. From the results, it was concluded that PEI loading influences the CO₂ capture performance, resulting from the enhancement of the basic functional groups on MCM-41.