Rapid synthesis of uniform silicalite-1 zeolite via a micro-liquid film reactor-assisted approach†

Abstract

In this work, silicalite-1 (S-1) zeolites with a uniform size of about 200 nm were rapidly synthesized by utilizing a micro-liquid film (MLF) reactor assisted hydrothermal method in a short period of 2 h, where the synthesis mixture solution underwent high-speed rotation and shear treatment in a thin liquid film zone within a short mixing time of 1–10 min at the premixing stage, yielding a homogeneous zeolite precursor colloidal suspension. It was revealed that the MLF reactor significantly enhanced the blending of the aqueous and organic phases containing the structure-directing agent and the silicon source, and the resulting homogeneous microenvironment of the zeolite precursor colloidal suspension facilitated the following hydrolysis process of the silicon source and polycondensation of initial structural units ([SiO₄]) to a large extent, thereby greatly accelerating nucleation and crystallization processes and thus yielding uniform S-1 zeolite crystals. The present findings provide a viable, economical, and scalable strategy for rapid synthesis of various zeolite materials applied in advanced heterogeneous catalytic reactions.