Synthesis of High Silica Zeolites Using a Mixed Quaternary Ammonium Cation, Amine Approach:  Discovery of Zeolite SSZ-47

A zeolite synthesis system is described in which a minor amount of structure-directing agent is used to specify the nucleation product, and then a larger amount of an amine is used to provide both pore filling and basicity capacities in the synthesis. A number of syntheses of different zeolite products are described for reactions in the SiO2/Al2O3 range of 35, which are conditions which yield high silica zeolites but are toward the more catalytically active end of the SiO2/Al2O3 spectrum. There are a number of cost-saving benefits described for this synthesis route including reduced structure-directing agent cost, waste stream cleanup costs, and time in reactor and reagent flexibility. Some details of the reaction are shown for this route to zeolite SSZ-25. The reaction was also used as a way to screen a new structure-directing agent, and zeolite SSZ-47 was discovered in this manner. The surprisingly high inorganic cation uptake in some of the zeolite products also may indicate that they play an important role in the stabilization and growth of structure-directing agent determined nuclei, particularly in syntheses under low structure-directing agent concentrations.