Ferrierite

Ferrierite

Ferrierite-Mg, Kamloops Lake, British Columbia, Canada
General
Category Zeolite
Formula
(repeating unit)
("A" position)3-5Mg[Al5-7Si27.5-31O72]·18H2O
Strunz classification 09.GD.50
Identification
Crystal system Orthorhombic

The ferrierite group of zeolite minerals (the FER structure) consists of three very similar species: ferrierite-Mg, ferrierite-Na, and ferrierite-K, based on the dominant cation in the A location. Ferrierites are orthorhombic minerals with highly variable cationic composition, (Na,K)2Mg(Si,Al)18O36(OH)·9H2O. Calcium and other ions are often also present. They are found in vitreous to pearly, often radiating, spherical aggregates of thin blade-shaped transparent to translucent crystals.

Ferrierite typically occurs as an alteration mineral in basaltic rocks and in tuffaceous sediments. In North America, it is found at Kamloops Lake, BC, Canada (the original type locality) and Leavitt Lake, California. Ferrierite was named for Canadian geologist and mining engineer Walter Frederick Ferrier (1865–1950).

Use

Synthetic ferrierites have even greater cation variability and have important uses as commercial filters and ion-exchange beds.

Ferrierite-H can be used as a catalyst in the chemical industry for the acid-catalyzed skeletal isomerization of n-butenes to isobutene, the raw material for production of methyl tert-butyl ether (MTBE).

See also

References

External links

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