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Zeolites are microporous,
aluminosilicate Aluminosilicate minerals are minerals composed of aluminium, silicon, and oxygen, plus countercations. They are a major component of kaolin and other clay minerals. Andalusite, kyanite, and sillimanite are naturally occurring aluminosilicate miner ...
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 ...

mineral
s commonly used as commercial
adsorbents of multilayer adsorption is a random distribution of molecules on the material surface. 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'' o ...

adsorbents
and
catalyst that utilizes a low-temperature oxidation catalyst to convert carbon monoxide to less toxic carbon dioxide at room temperature. It can also remove formaldehyde from the air. Catalysis () is the process of increasing the reaction rate, rate of a ...
s. The term ''zeolite'' was originally coined in 1756 by Swedish
mineralogist Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the processes ...

mineralogist
Axel Fredrik Cronstedt Baron Axel Fredrik Cronstedt (''/kroonstet/'' 23 December 1722 – 19 August 1765) was a Swedish mineralogist and chemist who discovered the element nickel in 1751 as a mining expert with the Bureau of Mines. Cronstedt is considered a founder of m ...
, who observed that rapidly heating the material, believed to have been
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 name ...
, produced large amounts of steam from water that had been
adsorbed of multilayer adsorption is a random distribution of molecules on the material surface. 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'' o ...

adsorbed
by the material. Based on this, he called the material ''zeolite'', from the
Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group *Greek language, a branch of the Indo-European language family **Proto-Greek language, the assumed last common ancestor of ...
, meaning "to boil" and , meaning "stone". The classic reference for the field has been Breck's book ''Zeolite Molecular Sieves: Structure, Chemistry, And Use''. Zeolites occur naturally but are also produced industrially on a large scale. , 245 unique zeolite frameworks have been identified, and over 40 naturally occurring zeolite frameworks are known. Every new zeolite structure that is obtained is examined by the International Zeolite Association Structure Commission and receives a three letter designation.


Properties and occurrence

Zeolites have a porous structure that can accommodate a wide variety of
cations An ion () is a particle, atom or molecule with a net electrical charge. The charge of the electron is considered negative by convention. The negative charge of an ion is equal and opposite to charged proton(s) considered positive by convent ...
, such as Na+, K+, Ca2+, Mg2+ and others. These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are
analcime Analcime or analcite (from the Greek ''analkimos'' - "weak") is a white, gray, or colorless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSi2O6·H2O. Minor am ...
,
chabazite Chabazite ()The New Oxford Dictionary of English (1998) - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.". is a tectosilicate mineral of the zeolite group, closely ...
,
clinoptilolite Clinoptilolite is a natural zeolite composed of a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na,K,Ca)2-3Al3(Al,Si)2Si13O36·12H2O. It forms as white, green to reddish tabular monoclinic tectosilicate cry ...
,
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 serie ...
,
natrolite Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula . The type locality is Hohentwiel, Hegau, Germany. It was named natrolite by Martin Heinrich Klaproth in ...
,
phillipsite Phillipsite is a mineral series of the zeolite group; a hydrated potassium, calcium and aluminium silicate, approximating to (Ca,Na2,K2)3Al6Si10O32·12H2O. The members of the series are phillipsite-K, phillipsite-Na and phillipsite-Ca. The crystals ...
, and
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 name ...
. An example of the mineral formula of a zeolite is: ·2H2O, the formula for
natrolite Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula . The type locality is Hohentwiel, Hegau, Germany. It was named natrolite by Martin Heinrich Klaproth in ...
. These cation exchanged zeolites possess different acidity and catalyse several acid catalysis. Natural zeolites form where
volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are d ...

volcanic
rocks and
ash Ash or ashes are the solid remnants of fires. Specifically, ''ash'' refers to all non-aqueous, non-gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is ...
layers react with
alkaline In chemistry, an alkali (; from ar, القلوي ''al-qaly'' "ashes of the saltwort") is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a solubl ...

alkaline
groundwater. Zeolites also crystallize in post-depositional environments over periods ranging from thousands to millions of years in shallow marine basins. Naturally occurring zeolites are rarely pure and are contaminated to varying degrees by other minerals, metals,
quartz Quartz is a hard, crystalline mineral composed of silicon and oxygen atoms. The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formul ...
, or other zeolites. For this reason, naturally occurring zeolites are excluded from many important commercial applications where uniformity and purity are essential. Zeolites are the
aluminosilicate Aluminosilicate minerals are minerals composed of aluminium, silicon, and oxygen, plus countercations. They are a major component of kaolin and other clay minerals. Andalusite, kyanite, and sillimanite are naturally occurring aluminosilicate miner ...
(AlO4^5- and SiO4^4-) members of the family of microporous solids known as "molecular sieves", and mainly consist of silicon, aluminum, oxygen, and metals, including titanium, tin, zinc, and so on. The term
molecular sieve A molecular sieve is a material with pores (very small holes) of uniform size. These pore diameters are similar in size to small molecules, and thus large molecules cannot enter or be adsorbed, while smaller molecules can. As a mixture of molecules ...
refers to a particular property of these materials, i.e., the ability to selectively sort molecules based primarily on a size exclusion process. This is due to a very regular pore structure of molecular dimensions. The maximum size of the molecular or ionic species that can enter the pores of a zeolite is controlled by the dimensions of the channels. These are conventionally defined by the ring size of the aperture, where, for example, the term "eight-ring" refers to a closed loop that is built from eight tetrahedrally coordinated silicon (or aluminium) atoms and eight oxygen atoms. These rings are not always perfectly symmetrical due to a variety of causes, including strain induced by the bonding between units that are needed to produce the overall structure, or coordination of some of the oxygen atoms of the rings to cations within the structure. Therefore, the pores in many zeolites are not cylindrical. Zeolites transform to other minerals under
weathering Weathering is the breaking down of rocks, soils, and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement), ...
,
hydrothermal alteration Metasomatism (from the Greek μετά (change) and σῶμα (body)) is the chemical alteration of a rock by hydrothermal and other fluids. It is the replacement of one rock by another of different mineralogical and chemical composition. The mineral ...
or
metamorphic#REDIRECT Metamorphic rock#REDIRECT Metamorphic rock#REDIRECT Metamorphic rock {{Redirect category shell, 1= {{R from other capitalisation ... {{Redirect category shell, 1= {{R from other capitalisation ...
{{Redirect category shell, 1= {{R f ...
conditions. Some examples: *The sequence of
silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...

silica
-rich
volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcanic ro ...

volcanic rock
s commonly progresses from: **
Clay Clay is a type of fine-grained natural soil material containing clay minerals. Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. ...

Clay
→ quartz →
mordenite Mordenite is a zeolite mineral with the chemical formula, (Ca, Na2, K2)Al2Si10O24·7H2O. 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 o ...
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 serie ...
epistilbite Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents and catalysts. The term ''zeolite'' was originally coined in 1756 by Swedish mineralogist Axel Fredrik Cronstedt, who observed that rapidly heating the mater ...
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 name ...
thomsonite Thomsonite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series ...
–mesolite-scolecite →
chabazite Chabazite ()The New Oxford Dictionary of English (1998) - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.". is a tectosilicate mineral of the zeolite group, closely ...
→ calcite. *The sequence of silica-poor volcanic rocks commonly progresses from: **Cowlesite → levyne–offretite →
analcime Analcime or analcite (from the Greek ''analkimos'' - "weak") is a white, gray, or colorless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSi2O6·H2O. Minor am ...
→ thomsonite–mesolite-scolecite → chabazite → calcite.


Production

Industrially important zeolites are produced synthetically. Typical procedures entail heating aqueous solutions of alumina and
silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...

silica
with sodium hydroxide. Equivalent reagents include sodium aluminate and sodium silicate. Further variations include the use of structure directing agents (SDA) such as quaternary ammonium cations. Synthetic zeolites hold some key advantages over their natural analogues. The synthetic materials are manufactured in a uniform, phase-pure state. It is also possible to produce zeolite structures that do not appear in nature. Zeolite A is a well-known example. Since the principal raw materials used to manufacture zeolites are silica and alumina, which are among the most abundant mineral components on earth, the potential to supply zeolites is virtually unlimited.


Natural occurrence

Conventional open-pit mining techniques are used to mine natural zeolites. The overburden is removed to allow access to the ore. The ore may be blasted or stripped for processing by using tractors equipped with ripper blades and front-end loaders. In processing, the ore is crushed, dried, and milled. The milled ore may be air-classified as to particle size and shipped in bags or bulk. The crushed product may be screened to remove fine material when a granular product is required, and some pelletized products are produced from fine material. the world's annual production of natural zeolite approximates 3 million tonnes. Major producers in 2010 included China (2 million tonnes), South Korea (210,000 t), Japan (150,000 t), Jordan (140,000 t), Turkey (100,000 t) Slovakia (85,000 t) and the United States (59,000 t). The ready availability of zeolite-rich rock at low cost and the shortage of competing minerals and rocks are probably the most important factors for its large-scale use. According to the United States Geological Survey, it is likely that a significant percentage of the material sold as zeolites in some countries is ground or sawn volcanic tuff that contains only a small amount of zeolites. Some examples of such usage include dimension stone (as an altered volcanic tuff), lightweight aggregate (composite), aggregate, Pozzolana, pozzolanic cement, and soil conditioners.


Artificial synthesis

There are over 200 synthetic zeolites that have been synthesized by a process of slow crystallization of a
silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...

silica
-alumina gel in the presence of alkalis and organic templates. Many more such structures could theoretically be made. In addition to variations in structures, zeolites can also be made with a variety of other atoms in them to make them chemically interesting and active. Some examples of the so-called heteroatoms that have been incorporated include germanium, iron, gallium, boron, zinc, tin, and titanium. One of the important processes used to carry out zeolite synthesis is sol-gel processing. The product properties depend on reaction mixture composition, pH of the system, operating temperature, pre-reaction 'seeding' time, reaction time as well as the templates used. In sol-gel process, other elements (metals, metal oxides) can be easily incorporated. The silicalite sol formed by the Hydrothermal synthesis, hydrothermal method is very stable. The ease of scaling up this process makes it a favorite route for zeolite synthesis.


The zeolite conundrum

Computer calculations have predicted that millions of hypothetical zeolite structures are possible. However, only 232 of these structures have been discovered and synthesized so far, so many zeolite scientists question why only this small fraction of possibilities are being observed. This problem is often referred to as "the bottleneck problem". Currently there are a number of theories attempting to explain the reasoning behind this question. # Zeolite synthesis research has primarily been concentrating on hydrothermal methods; however, new zeolites may be synthesized using alternative methods. Synthesis methods that have started to gain use include: microwave-assisted, post-synthetic modification, steam. # Geometric computer simulations have shown that the discovered zeolite frameworks possess a behaviour known as "the flexibility window". This shows that there is a range in which the zeolite structure is "flexible" and can be compressed but retain the framework structure. It is suggested that if a framework does not possess this property then it cannot be feasibly synthesised. # As zeolites are metastable, certain frameworks may be inaccessible as nucleation cannot occur because more stable and energetically favourable zeolites will form. Post-synthetic modification has been used to combat this issue with the ADOR method, whereby frameworks can be cut apart into layers and bonded back together by either removing silica bonds or including them.


Uses of zeolites

Zeolites are widely used as ion-exchange beds in domestic and commercial water purification, softening, and other applications. In chemistry, zeolites are used to separate molecules (only molecules of certain sizes and shapes can pass through), and as traps for molecules so they can be analyzed. Zeolites are also widely used as catalysts and sorbents. Their well-defined pore structure and adjustable acidity make them highly active in a large variety of reactions. Zeolites have the potential of providing precise and specific separation of gases, including the removal of H2O, CO2, and SO2 from low-grade natural gas streams. Other separations include noble gases, N2, O2, freon, and formaldehyde. Zeolites were discovered to help silver naturally emit light, which may compete with fluorescent lights or LEDs. On-board oxygen generating systems (OBOGS) and oxygen concentrators use zeolites in conjunction with pressure swing adsorption to remove nitrogen from compressed air to supply oxygen for aircrews at high altitudes, as well as home and portable oxygen supplies.


Industry

Synthetic zeolites, like other mesoporous materials (e.g. MCM-41), are widely used as catalysts in the petrochemical industry, such as in fluid catalytic Cracking (chemistry), cracking and hydrocracking. Zeolites confine molecules into small spaces, which causes changes in their structure and reactivity. The acidic forms of zeolites prepared are often powerful solid-state solid acids, facilitating a host of acid-catalyzed reactions, such as isomerisation, alkylation, and cracking. Catalytic cracking uses a reactor and a regenerator. Feed is injected onto a hot, fluidized catalyst where large gasoil molecules are broken into smaller gasoline molecules and olefins. The vapor-phase products are separated from the catalyst and distilled into various products. The catalyst is circulated to a regenerator, where air is used to burn coke off the surface of the catalyst that was formed as a byproduct in the cracking process. The hot, regenerated catalyst is then circulated back to the reactor to complete its cycle. Zeolites have uses in advanced nuclear-waste reprocessing methods, where their micro-porous ability to capture some ions while allowing others to pass freely allows many fission products to be efficiently removed from the waste and permanently trapped. Equally important are the mineral properties of zeolites. Their alumino-silicate construction is extremely durable and resistant to radiation, even in porous form. Additionally, once they are loaded with trapped fission products, the zeolite-waste combination can be hot pressed into an extremely durable ceramic form, closing the pores and trapping the waste in a solid stone block. This is a waste form factor that greatly reduces its hazard, compared to conventional reprocessing systems. Zeolites are also used in the management of leaks of radioactive materials. For example, in the aftermath of the Fukushima Daiichi nuclear disaster, sandbags of zeolite were dropped into the seawater near the power plant to adsorb the radioactive caesium that was present in high levels. The German group Fraunhofer Society, Fraunhofer e.V. announced that they had developed a zeolite substance for use in the biogas industry for long-term storage of energy at a density four times greater than water. Ultimately, the goal is to store heat both in industrial installations and in small combined heat and power plants such as those used in larger residential buildings.


Solar energy storage and use

Zeolites can be used to thermochemically store solar heat harvested from solar thermal collectors as first taught by Guerra in 1978 and for adsorption refrigeration, as first taught by Tchernev in 1974. In these applications, their high heat of adsorption and ability to hydrate and dehydrate while maintaining structural stability is exploited. This hygroscopic property coupled with an inherent exothermic (energy releasing) reaction when transitioning from a dehydrated form to a hydrated form make natural zeolites useful in harvesting waste heat and solar heat energy.


Commercial and domestic

Zeolites are also used as a
molecular sieve A molecular sieve is a material with pores (very small holes) of uniform size. These pore diameters are similar in size to small molecules, and thus large molecules cannot enter or be adsorbed, while smaller molecules can. As a mixture of molecules ...
in cryopump, cryosorption style vacuum pumps. The largest single use for zeolite is the global laundry detergent market. This amounted to 1.44 million metric tons per year of anhydrous zeolite A in 1992. Non-clumping cat litter is often made of zeolite or diatomite. Synthetic zeolites are used as an additive in the production process of warm mix asphalt concrete. The development of this application started in Germany in the 1990s. They help by decreasing the temperature level during manufacture and laying of asphalt concrete, resulting in lower consumption of fossil fuels, thus releasing less carbon dioxide, aerosols, and vapours. The use of synthetic zeolites in hot mixed asphalt leads to easier compaction and, to a certain degree, allows cold weather paving and longer hauls. When added to Portland cement as a pozzolan, they can reduce chloride permeability and improve workability. They reduce weight and help moderate water content while allowing for slower drying, which improves break strength. When added to lime mortars and lime-metakaolin mortars, synthetic zeolite pellets can act simultaneously as a pozzolanic material and a water reservoir. Debbie Meyer Green Bags, a produce storage and preservation product, uses a form of zeolite as its active ingredient. The bags are lined with zeolite to adsorb ethylene, which is intended to slow the ripening process and extend the shelf life of produce stored in the bags.


Gemstones

Thomsonites, one of the rarer zeolite minerals, have been collected as gemstones from a series of lava flows along Lake Superior in Minnesota and, to a lesser degree, in Michigan, U.S.. Thomsonite nodules from these areas have erosion, eroded from basalt lava flows and are collected on beaches and by scuba divers in Lake Superior. These thomsonite nodules have concentric rings in combinations of colors: black, white, orange, pink, purple, red, and many shades of green. Some nodules have copper inclusions and rarely will be found with copper "eyes". When polished by a lapidary, the thomsonites sometimes displays a "cat's eye" effect (chatoyancy).


Biological

Research into and development of the many biochemical and biomedical applications of zeolites, particularly the naturally occurring species
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 serie ...
,
clinoptilolite Clinoptilolite is a natural zeolite composed of a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na,K,Ca)2-3Al3(Al,Si)2Si13O36·12H2O. It forms as white, green to reddish tabular monoclinic tectosilicate cry ...
, and
chabazite Chabazite ()The New Oxford Dictionary of English (1998) - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.". is a tectosilicate mineral of the zeolite group, closely ...
has been ongoing. Zeolite-based oxygen concentrator systems are widely used to produce medical-grade oxygen. The zeolite is used as a molecular sieve to create purified oxygen from air using its ability to trap impurities, in a process involving the adsorption of nitrogen, leaving highly purified oxygen and up to 5% argon. QuikClot brand Hemostatic agents, hemostatic agent, which is used to stop severe bleeding, contains a calcium-loaded form of zeolite found in kaolin clay. In agriculture,
clinoptilolite Clinoptilolite is a natural zeolite composed of a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na,K,Ca)2-3Al3(Al,Si)2Si13O36·12H2O. It forms as white, green to reddish tabular monoclinic tectosilicate cry ...
(a naturally occurring zeolite) is used as a soil treatment. It provides a source of slowly released potassium. If previously loaded with ammonium, the zeolite can serve a similar function in the slow release of nitrogen. Zeolites can also act as water moderators, in which they will absorb up to 55% of their weight in water and slowly release it under the plant's demand. This property can prevent root rot and moderate drought cycles. Clinoptilolite has also been added to chicken food: the absorption of water and ammonia by the zeolite made the birds' droppings drier and less odoriferous, hence easier to handle. Pet stores market zeolites for use as filter additives in aquarium, aquaria, where they can be used to adsorb ammonia and other nitrogenous compounds. They must be used with some care, especially with delicate tropical corals that are sensitive to water chemistry and temperature. Due to the high affinity of some zeolites for calcium, they may be less effective in hard water and may deplete calcium. Zeolite filtration is also used in some marine aquaria to keep nutrient concentrations low for the benefit of corals adapted to nutrient-depleted waters. Where and how the zeolite was formed is an important consideration for aquarium applications. Most Northern hemisphere, natural zeolites were formed when molten lava came into contact with sea water, thereby "loading" the zeolite with Na (sodium) sacrificial ions. The mechanism is well known to chemists as ion exchange. These sodium ions can be replaced by other ions in solution, thus the takeup of nitrogen in ammonia, with the release of the sodium. A deposit near Bear River (Great Salt Lake), Bear River in southern Idaho is a fresh water variety (Na < 0.05%). Southern hemisphere zeolites are typically formed in freshwater and have a high calcium content.


Zeolite mineral species

The zeolite structural group (Nickel-Strunz classification) includes: * 09.GA. - Zeolites with T5O10 units (T = combined Si and Al) – the fibrous zeolites **Natrolite framework (NAT): gonnardite,
natrolite Natrolite is a tectosilicate mineral species belonging to the zeolite group. It is a hydrated sodium and aluminium silicate with the formula . The type locality is Hohentwiel, Hegau, Germany. It was named natrolite by Martin Heinrich Klaproth in ...
, mesolite, paranatrolite, scolecite, tetranatrolite **Edingtonite framework (EDI): edingtonite, kalborsite **Thomsonite framework (THO):
thomsonite Thomsonite is the name of a series of tecto-silicate minerals of the zeolite group. Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series ...
-series * 09.GB. - Chains of single connected 4-membered rings **Analcime framework (ANA):
analcime Analcime or analcite (from the Greek ''analkimos'' - "weak") is a white, gray, or colorless tectosilicate mineral. Analcime consists of hydrated sodium aluminium silicate in cubic crystalline form. Its chemical formula is NaAlSi2O6·H2O. Minor am ...
, leucite, pollucite, wairakite **Laumontite (LAU), yugawaralite (YUG), goosecreekite (GOO), montesommaite (MON) * 09.GC. - Chains of doubly connected 4-membered rings **Phillipsite framework (PHI): harmotome,
phillipsite Phillipsite is a mineral series of the zeolite group; a hydrated potassium, calcium and aluminium silicate, approximating to (Ca,Na2,K2)3Al6Si10O32·12H2O. The members of the series are phillipsite-K, phillipsite-Na and phillipsite-Ca. The crystals ...
-series **Gismondine framework (GIS): amicite, gismondine, garronite, gobbinsite **Boggsite (BOG), merlinoite (MER), mazzite-series (MAZ), paulingite-series (PAU), perlialite (Linde type L framework, zeolite L, LTL) * 09.GD. - Chains of 6-membered rings – tabular zeolites **Chabazite framework (CHA):
chabazite Chabazite ()The New Oxford Dictionary of English (1998) - p. 300 "chabazite /'kabəzʌɪt/ noun "A colourless, pink or yellow zeolite mineral, typically occurring as rhombohedral crystals.". is a tectosilicate mineral of the zeolite group, closely ...
-series, herschelite, willhendersonite and SSZ-13 **Faujasite framework (FAU): faujasite-series, Linde type X (zeolite X, X zeolites), Linde type Y (zeolite Y, Y zeolites) **Mordenite framework (MOR): maricopaite,
mordenite Mordenite is a zeolite mineral with the chemical formula, (Ca, Na2, K2)Al2Si10O24·7H2O. 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 o ...
**Offretite–wenkite subgroup 09.GD.25 (Nickel–Strunz, 10 ed): offretite (OFF), wenkite (WEN) **Bellbergite (TMA-E, Aiello and Barrer; framework type EAB), bikitaite (BIK), erionite-series (ERI), ferrierite (FER), gmelinite (GME), levyne-series (LEV), dachiardite-series (DAC),
epistilbite Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents and catalysts. The term ''zeolite'' was originally coined in 1756 by Swedish mineralogist Axel Fredrik Cronstedt, who observed that rapidly heating the mater ...
(EPI) * 09.GE. - Chains of T10O20 tetrahedra (T = combined Si and Al) **Heulandite framework (HEU):
clinoptilolite Clinoptilolite is a natural zeolite composed of a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na,K,Ca)2-3Al3(Al,Si)2Si13O36·12H2O. It forms as white, green to reddish tabular monoclinic tectosilicate cry ...
,
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 serie ...
-series **Stilbite framework (STI): barrerite, stellerite,
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 name ...
-series **Brewsterite framework (BRE): brewsterite-series * Others **Cowlesite, pentasil (also known as ZSM-5, framework type MFI), tschernichite (beta polymorph A, disordered framework, BEA), Linde type A framework (zeolite A, LTA)


See also

*, the amorphous alumino-silicate equivalent of zeolite * * * * *


References

*


Further reading

* * * * * *


External links


International Zeolite AssociationDatabase of zeolite pore characterizationsThe Synthesis Commission of the International Zeolite AssociationFederation of European Zeolite AssociationsBritish Zeolite Association

Database of Zeolite Structures
{{Authority control Zeolites Tectosilicates Antihemorrhagics Conservation and restoration materials Porous media Industrial minerals Catalysts Acid catalysts