Synthesis and characterization of MCM-41 mesoporous molecular sieves ontaining Zirconium and Iron

MCM-41 mesoporous molecular sieves containing Zirconium and Iron with different metal contents were synthesized by means of hydrothermal treatment using the method of direct insertion of metal ions as precursors in the initial stage of synthesis. The physicochemical properties of the materials were thoroughly investigated employing X-ray powder diffraction, SEM, TGA, FTIR and N2 adsorption–desorption methods. The results indicated that MCM-41 materials with long range hexagonal ordering could be successfully synthesized by the hydrothermal method in the presence of Zirconium and Iron salts with the Si/(Zr+Fe) molar ratio equal to 31 and 61.%. A further increase in the metal content deteriorated the ordering of the materials. The morphology of Zr–Fe-MCM-41 and Zr-MCM-41 materials was determined by SEM. The incorporated metal ions, i.e. Zr4+, Fe2+ and Fe3+ in Zr–Fe-MCM-41 are coordinated to Si(IV) by tetrahedral, disordered octahedral and tetrahedral environments, respectively. The zirconium and iron ions are homogenously dispersed on the internal silica surface of the Zr–Fe-MCM-41.

کلیدواژه ها:

Mesoporous ، molecular sieve ، Zr- MCM-41 ، Zr-Fe- MCM-41 ، hydrothermal