The role of short order in embryonic CHA precursor on its effective steam-assisted conversion to a fully crystalline zeolite

Abstract

Zeolites, particularly SSZ-13 with CHA topology, are widely used in industrial catalytic processes due to their confined Brønsted acid sites within microporous networks, enabling unique chemical reactions such as methanol-to-olefins (MTO) conversion. Nonetheless, there are still challenges in synthesizing chabazite-based catalysts, including high costs associated with organic structural directing agents and lengthy hydrothermal crystallization periods. Herein, we used a dry-gel precursor, allowing rapid zeolite formation, using the steam-assisted crystallization (SAC) route, elucidating the key steps that promote faster CHA zeolite precursors’ crystallization. Our results demonstrate that preparing a well-ordered dry-gel precursor containing embryonic units is critical in achieving efficient CHA zeolite formation. This research elucidates zeolite crystallization kinetics in the SAC method and offers a pathway for further studies to optimize OSDA usage or explore template-free synthesis methods based on the rational design of an embryonic CHA zeolite.