SYNTHESIS AND CHARACTERIZATION OF PURE-SILICA AND BORON-SUBSTITUTED SSZ-24 USING N(16) METHYLSPARTEINIUM BROMIDE AS STRUCTURE-DIRECTING AGENT

SSZ-24, the high-silica molecular sieve isostructural with AlPO4-5 (AFI), is synthesized using N(16) methylsparteinium bromide as structure-directing agent and is characterized using X-ray powder diffraction (XRD), magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy and the physical adsorption of N2. Unlike other structure-directing agents used for the synthesis of SSZ-24, N(16) methylsparteinium allows for the direct incorporation of boron into the zeolite framework using sodium borate as the source of boron in the synthesis medium. Boron can be removed from the structure and replaced by aluminum by refluxing the calcined sample in an aluminum nitrate solution. It is speculated that the incorporation of boron in the framework is related to the hydrophobicity of the sparteinium cation.