zeoliittia

Zeoliittia is the Finnish term for zeolites, a family of microporous aluminosilicate minerals known for their three‑dimensional framework of silicon and aluminum tetrahedra linked by shared oxygen atoms. The negative framework charge is balanced by exchangeable cations such as sodium, potassium, or calcium, which enables ion exchange and gas or water molecule adsorption within a system of uniform pores and channels.

The characteristic porous structure gives zeolites high selectivity for ions and molecules based on size and shape. They typically contain water in their cavities, which can be lost upon heating. Zeolites are chemically stable over a range of conditions and can function as catalysts, adsorbents, or ion-exchange materials.

Natural occurrences occur in volcanic and sedimentary environments, often forming from the alteration of volcanic ash or tuff in hydrothermal conditions. Common naturally occurring zeolites include clinoptilolite, chabazite, mordenite, and analcime. Natural zeolites are mined and used directly for applications such as water purification, soil amendment, and odor control, though many industrial uses rely on synthetic varieties.

Synthetic zeolites are produced industrially by hydrothermal synthesis from aluminosilicate gels, allowing control over the silicon-to-aluminum ratio and the pore structure. This enables tailored catalysts (for example, zeolite Y and ZSM-5) and ion-exchange materials for detergents, petrochemical processing, gas separation, and environmental remediation. Zeolites are valued for their regenerable, selective performance and wide range of industrial applications.

The term zeolite derives from Greek roots meaning “to boil stone,” reflecting the release of water from the mineral upon heating, a naming choice attributed to the mineralogist Axel Cronstedt in the 18th century.