Zeoliittipohjaisia

Zeoliittipohjaisia refers to materials based on zeolites. Zeolites are a group of porous crystalline aluminosilicate minerals. They have a unique three-dimensional framework structure formed by silicon-oxygen and aluminum-oxygen tetrahedra. This structure contains interconnected cavities and channels of molecular dimensions.

The key characteristic of zeolites is their ability to undergo ion exchange. The aluminum atoms in the framework carry a negative charge, which is balanced by mobile cations, typically alkali or alkaline earth metals. These cations can be exchanged with other ions in a solution, making zeolites useful as ion exchangers. This property is widely utilized in water softening, where calcium and magnesium ions are replaced by sodium ions.

Zeolites also exhibit adsorption properties due to their porous structure. They can selectively adsorb molecules based on their size and polarity, allowing them to act as molecular sieves. This makes them valuable in separation processes, such as the purification of gases and liquids, and in the removal of pollutants.

Furthermore, zeolites can function as catalysts. Their acidic sites, arising from the framework's structure and the presence of protons, can catalyze various chemical reactions, including cracking, isomerization, and alkylation in the petrochemical industry. The specific pore size and structure can also influence the selectivity of these catalytic processes.

In summary, zeoliittipohjaisia materials leverage the inherent properties of zeolites, namely ion exchange, adsorption, and catalytic activity, for a wide range of industrial and environmental applications.