Synthesis, characterization, and catalytic properties of stable mesoporous alumino silicates assembled from preformed zeolite L precursors

Ordered mesoporous aluminosilicates designated as MAS-3 and MAS-8 with hexagonal mesopores have been hydrothermally synthesized from preformed zeolite L precursors under alkaline and strongly acidic conditions, respectively. MAS-3 and MAS-8 show good thermal and hydrothermal stability. Catalytic results in cracking cumene show that these mesoporous aluminosilicates are more active than conventional mesoporous aluminosilicates (Al-MCM-41). Characterization of infrared, N-2 adsorption isotherms, and temperature-programmed-desorption of ammonia (NH3-TPD) have also been used to investigate these materials and the results indicate that the walls of MAS-3 and MAS-8 contain the primary and secondary structural building units, which might be responsible for the high hydrothermal stability and good activities in catalysis. (C) 2003 Elsevier Inc. All rights reserved.