Mordenite is a
zeolite
Zeolites are microporous, crystalline aluminosilicate materials commonly used as commercial adsorbents and catalysts. They mainly consist of silicon, aluminium, oxygen, and have the general formula ・y where is either a metal ion or H+. These p ...
mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...
with the chemical formula, (
Ca,
Na2,
K2)
Al2 Si10 O24·7
H2O. and it is one of the six most abundant zeolites and is used commercially.
It was first described in 1864 by
Henry How. He named it after the small community of
Morden, Nova Scotia,
Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, along the
Bay of Fundy, where it was first found.
Mordenite is
orthorhombic (a,b,c unequal & all angles 90 degree). It crystallizes in the form of fibrous aggregates, masses, and vertically striated prismatic crystals. It may be colorless, white, or faintly yellow or pink. It has
Mohs hardness of 5 and a density of 2.1 g/cm
3. When it forms well developed crystals they are hairlike; very long, thin, and delicate.
[Mindat with location data]
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Mordenite’s molecular structure is a framework containing chains of five-membered rings of linked silicate and aluminate tetrahedra (four oxygen atoms arranged at the points of a triangular pyramid about a central silicon or aluminium atom). Its high ratio of silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic ta ...
to aluminum
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...
atoms makes it more resistant to attack by acids than most other zeolites.
Mordenite is one of the most abundant zeolites in altered volcanic deposits; it is found in volcanic rock such as rhyolite, andesite
Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predo ...
, and basalt
Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...
. It is associated with other zeolites such as stilbite
Stilbite is the name of a series of tectosilicate minerals of the zeolite group. Prior to 1997, stilbite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series na ...
and heulandite
Heulandite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, heulandite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a ser ...
. Good examples have been found in Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...
, India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
, Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...
, Oregon
Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...
, Washington, and Idaho
Idaho ( ) is a state in the Pacific Northwest region of the Western United States. To the north, it shares a small portion of the Canada–United States border with the province of British Columbia. It borders the states of Montana and Wyomi ...
.[ It is also found in marine sediments, as in the Ural Mountains and in dikes where water has attacked and altered volcanic glasses, as on the Isle of Arran in Scotland.]["mordenite"]
Encyclopædia Britannica. 2009. Encyclopædia Britannica Online. Access date 15 Apr. 2009
Use
* Synthetic Mordenite is used as a catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
in the petrochemical industry for the acid-catalyzed isomerisation of alkanes
In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in whi ...
and aromatics
Aromatic compounds, also known as "mono- and polycyclic aromatic hydrocarbons", are organic compounds containing one or more aromatic rings. The parent member of aromatic compounds is benzene. The word "aromatic" originates from the past groupin ...
.
* In New Zealand mordenite-bearing zeolitic tuff is dried and crushed to produce a variety of products including adsorbent
Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. This process creates a film of the ''adsorbate'' on the surface of the ''adsorbent''. This process differs from absorption, in which a f ...
s for soaking up oil/chemical spills and animal wastes, animal feed supplements, water treatment, and sports turf and slow release fertilizer.
* Sedimentary deposits of mordenite are present in several countries, especially in Bulgaria, Hungary, Japan and the United States. Quarried material is generally substantial, e.g., a recent estimate of the yearly production in Japan is 150,000 tons.
* Apart from generic applications in the fields of agriculture and building industry (as dimension stone), uses are known as sorbent and molecular sieve
*Gas separation
Gas separation can refer to any of a number of techniques used to separate gases, either to give multiple products or to purify a single product.
Swing adsorption techniques
Pressure swing adsorption
Pressure swing adsorption (PSA) pressurize ...
processes are reported for the production of high-grade O2 from air by pressure-swing operating generators. Full-scale plants based on mordenite-rich tuffs have been operating in Japan since the end of the 1960.
References
{{reflist
External links
Structure type MOR
Calcium minerals
Sodium minerals
Potassium minerals
Aluminium minerals
Zeolites
Orthorhombic minerals
Minerals in space group 36