An efficient one-pot strategy for synthesizing hierarchical aluminosilicate zeolites using single structure directing agent

Abstract

Hierarchical aluminosilicate zeolites were simply synthesized by a temperature-gradient strategy using conventional CTAB as single structure directing agent. The as-synthesized zeolites were composed of an ordered two-dimensional hexagonal mesopores and crystallized MFI structure. Catalytic performance of the hierarchical aluminosilicate zeolites were explored by the Claisen-Schmidt condensation of bulky reactants (benzaldehyde and 2′-hydroxyacetophenone). The reaction results showed that the hierarchical zeolites exhibit outstanding catalytic performance with a conversion as high as 73%, which may be attributed to the combined advantage of framework acidity of zeolite and the significantly improved large molecule diffussion in mesoporosity. The higher hydrothermal stability and catalytic stability than those of MCM-41 samples were proved, which were ascribed to the presence of crystallized MFI structure.