zeolitebased

Zeolite-based materials are substances that incorporate zeolites as a key component, either as discrete zeolite crystals embedded in a matrix, as zeolite frameworks used as solid catalysts, or as zeolite-derived composites. Zeolites are microporous aluminosilicate minerals with a rigid crystal framework formed by interconnected SiO4 and AlO4 tetrahedra, creating uniform channels and cavities. The framework carries negative charge balanced by extra-framework cations, which can be exchanged to tune acidity and sorption properties. Typical pore systems deliver pore sizes in the range of 0.3 to 1.5 nanometers, enabling molecular sieving and shape selectivity, while high surface area supports rapid mass transport in the pores.

Zeolites are chemically and thermally stable under many hydrocarbon processing conditions, making them valuable as solid acid catalysts, particularly in petroleum refining and petrochemical synthesis, including cracking, isomerization, alkylation, and methanol-to-hydrocarbons routes. In adsorption and separation, zeolites selectively adsorb molecules based on size, shape, and polarity, enabling gas separations, dehydration, and CO2 capture. Zeolite-based composites combine zeolites with polymers, metals, or other oxides to improve processability, mechanical strength, or introduce multifunctional properties such as bifunctionality or enhanced diffusion.

Synthesis typically involves hydrothermal crystallization from silicon and aluminum sources, structure-directing agents, and mineralizers, with post-synthesis modifications including ion exchange, dealumination, or desilication to tailor acidity and porosity. Research continues toward hierarchical zeolites with mesopores, stable under harsh conditions, and scalable routes to tailor pore architecture for specific applications. Environmental and safety considerations focus on powder handling and waste streams in production.