THE SYNTHESIS AND CHARACTERIZATION OF MESOPOROUS MOLECULAR-SIEVES MCM-41

Mesoporous molecular sieve MCM-41 and a mesoporous MCM-41-like solid were synthesized with organic surfactant CnH2n+1(CH3)(3)NX (n=12,16) as the templates by hydrothermal synthesis or direct synthesis at room temperature. The synthesis conditions and crystallization were investigated. Some hydrothermally synthesized products are proved to be amorphous by XRD determination, while after calcination they turned to mesoporous materials with high crystallinity. The structure and property of the two phases were studied by means of XRD, IR, TG and adsorption techniques. The results show that the two materials have the same physical and chemical qualities. The inorganic portion of them resembles amorphous silicates or aluminosilicates rather than crystalline molecular sieves.