Zeolite Blending: A New Approach to Direct Crystallization of Aluminosilicate Zeolite

Various synthesis methods for zeolites have been developed to date; however, precise control over aluminum (Al) content remains a significant challenge. For instance, in the case of CON-type zeolites, it is especially difficult to obtain a Si/Al ratio below a value of approximately 100 by direct synthesis, and below approximately 30 by post-treatment. In this study, we have developed a novel direct synthesis method of the CON-type zeolite having desired Al content by applying the interzeolite conversion/interzeolite transformation, wherein precursor zeolites that possess common composite building units (CBUs) with the target zeolite are employed as the Al and Si source. Initially, a single zeolite was utilized as a precursor, resulting in the successful synthesis of a high Al CON-type zeolite (Si/Al=40). Finally, we developed a novel synthesis method of the CON-type zeolite; blending of two types of zeolites, MFI and Beta, as starting material in the IZC method led to the direct crystallization of the CON-type aluminosilicate with high Al content (Si/Al=20).