Synthesis of MgO-Modified Mesoporous Silica and Its Adsorption Performance toward CO_2

摘要

The mesoporous silica modified with magnesium oxide(MgO) was synthesized by one step method and impregnating method,respectively.The samples were characterized by small angle X-Ray diffraction(XRD),N_2 adsorption-desorption and transmission electron microscopy(TEM),and the carbon dioxide adsorption capacity was analyzed by thermal gravimetric analysis(TGA).Compared with the original mesoporous silica(20.7 mg/g),the CO_2 adsorption capacity of MgO-modified mesoporous silica processed by one step method increases to 32.9 mg/g.Although its surface area greatly decreases compared with that of the original mesoporous silica,the MgO-modified mesoporous silica prepared by impregnating reaches an adsorptive value of 31.1 mg/g because the number of basic sites increases on the surface of the mesoporous silica.