Aluminosilicatebased

Aluminosilicate-based materials are a class of inorganic compounds consisting of aluminum, silicon, and oxygen arranged in network structures. In these materials, silicon and aluminum are coordinated by oxygen in tetrahedral units [SiO4] and [AlO4], linked to form three-dimensional frameworks. Substitution of aluminum for silicon introduces negative framework charges, which are balanced by extra-framework cations such as sodium, potassium, calcium, or organic cations that may reside in pores or interlayers. This family includes naturally occurring clays as well as synthetic crystalline materials known as zeolites and other porous aluminosilicates.

The defining features of aluminosilicate-based materials are their framework topology, porosity, and acidity. Zeolites exhibit well-defined microporosity with uniform pore sizes and high diffusion rates, enabling selective adsorption and catalysis. Layered aluminosilicates, such as clays (for example, montmorillonite and illite), have expandable interlayers that can intercalate water and other species. The acidity arising from framework aluminum provides Bronsted or Lewis acid sites after appropriate treatment, which is central to catalytic activity. Ion exchange capacity and thermal stability are additional important properties.

Synthesis methods include hydrothermal crystallization to form crystalline zeolites, sol-gel processing, and top-down or bottom-up approaches to create mesoporous variants. Si/Al ratio, presence of structure-directing agents, and the choice of balancing cations influence porosity, acidity, and stability. Natural clays occur widely and are processed for industrial use, while synthetic aluminosilicates are tailored for specific applications.

Applications span catalysis, adsorption and separation, ion exchange, and environmental remediation. They are used as catalysts for petroleum refining and chemical synthesis, as adsorbents for gases and contaminants, and as components in materials like detergents, ceramics, and polymer composites. Safety and environmental considerations focus on dust management and proper handling of fine particles.