Synthesis, structure, and physicochemical and catalytic characterization of the novel high-silica large-pore zeolite SSZ-42

The novel high-silica zeolite SSZ-42 was synthesized and characterized by X-ray diffraction, scanning electron micrographs, transmission electron micrographs, argon and hydrocarbon adsorption, elemental analysis, C-13 MAS NMR, FTIR, and catalytic reactions. The framework topology of SSZ-42 has been determined from X-ray diffraction data taken from a small single crystal (15 x 15 x 35 mu m) and refined from powder diffraction data. The crystalline architecture is characterized by an undulating, one-dimensional 12-membered T-atom ring (12-MR) channel system. This configuration is a surprise given that the measured adsorption capacity is much higher than expected for a one-dimensional channel system. The material is stable up to at least 800 degrees C under thermal and hydrothermal conditions. and exhibits many interesting characteristics and promises to be a useful catalyst for hydrocarbon processing.