Synthesis of SFH-type aluminosilicate zeolite with 14-membered ring and its applications as solid acidic catalyst

Abstract

The direct-synthesis method for preparing the SFH-type aluminosilicate zeolites, designated as [Al,B]-SFH-D, was successfully improved by adding the calcined SFH-type borosilicate zeolite as seeds into the mother gel in the presence of N,N,N-trimethyl-phenylcyclohexylmethylammonium hydroxide as organic-structure-directing agent. As a control, by the conventional post-synthesis method, the SFH-type aluminosilicate zeolites, designated as [Al,B]-SFH-P, were prepared. Thus prepared SFH-type aluminosilicate zeolites were characterized in details. The high-resolution 27Al MAS NMR results implied that there are marked differences in the distribution of Al atoms in the framework between the zeolites obtained by the direct- and post-synthesis methods. [Al,B]-SFH-D exhibited a higher catalytic performance in the acylation of 2-methoxynaphthalene with acetic anhydride than [Al,B]-SFH-P.