| Abstract
| - The role of structure-directing agents (SDA) in the synthesis of zeolites is investigated, and the structuresobtained in the synthesis are rationalized in terms of the energetic stabilization between the SDA and themicroporous zeolite structure. An explanation is provided for the synthesis outcome in terms of a balancebetween kinetic and thermodynamic factors throughout the nucleation and crystallization stages. The stabilityof β, EU-1, ZSM-11, and ZSM-12 zeolites is calculated over a wide range of Si/Al ratios when cyclohexylalkyl pyrrolidinium salts are used as the SDA. The role of the SDA allows us to explain the final stability andthe Si/Al range in which each structure can be synthesized. The stabilization of intermediate species duringthe nucleation is proposed to orient the final result of the synthesis. A simple kinetic model is proposed toexplain the synthesis process.
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