Smectite wiki

Montmorillonite is a very soft phyllosilicate group of minerals that form when they precipitate from water solution as microscopic crystalsknown as clay. It is named after Montmorillon in France. Montmorillonite, a member of the smectite group, is a clay, meaning that it has two tetrahedral sheets of silica sandwiching a central octahedral sheet of alumina.

Members of this group include, amongst others, saponitenontronitebeidelliteand hectorite. The substitution of lower valence cations in such instances leaves the nearby oxygen atoms with a net negative charge that can attract cations.

The individual crystals of montmorillonite clay are not tightly bound hence water can intervene, causing the clay to swell.

smectite wiki

The water content of montmorillonite is variable and it increases greatly in volume when it absorbs water. Chemically, it is hydrated sodium calcium aluminium magnesium silicate hydroxide Na,Ca 0. Potassium, iron, and other cations are common substitutes, and the exact ratio of cations varies with source.

smectite wiki

It often occurs intermixed with chloritemuscoviteillitecookeiteand kaolinite. Montmorillonite can be concentrated and transformed within cave environments. The natural weathering of the cave can leave behind concentrations of aluminosilicates which were contained within the bedrock. Montmorillonite can form slowly in solutions of aluminosilicates. Montmorillonite is used in the oil drilling industry as a component of drilling mudmaking the mud slurry viscouswhich helps in keeping the drill bit cool and removing drilled solids.

It is also used as a soil additive to hold soil water in drought-prone soils, used in the construction of earthen dams and leveesand to prevent the leakage of fluids. It is also used as a component of foundry sand and as a desiccant to remove moisture from air and gases. Montmorillonite clays have been extensively used in catalytic processes. Cracking catalysts have used montmorillonite clays for over 60 years.

Other acid-based catalysts use acid-treated montmorillonite clays. Similar to many other clays, montmorillonite swells with the addition of water. Montmorillonites expand considerably more than other clays due to water penetrating the interlayer molecular spaces and concomitant adsorption. The amount of expansion is due largely to the type of exchangeable cation contained in the sample.

The presence of sodium as the predominant exchangeable cation can result in the clay swelling to several times its original volume. Hence, sodium montmorillonite has come to be used as the major constituent in nonexplosive agents for splitting rock in natural stone quarries in an effort to limit the amount of waste, or for the demolition of concrete structures where the use of explosive charges is unacceptable.

This swelling property makes montmorillonite-containing bentonite useful also as an annular seal or plug for water wells and as a protective liner for landfills. Other uses include as an anticaking agent in animal feed, in papermaking to minimize deposit formation, and as a retention and drainage aid component.

Montmorillonite has also been used in cosmetics. In a fine powder form, it can also be used as a flocculant in ponds. Tossed on the surface as it drops into the water, making the water "clouded", it attracts minute particles in the water and then settles to the bottom, cleaning the water.

Clay minerals

Koi and goldfish carp then actually feed on the "clump" which can aid in the digestion of the fish. It is sold in pond supply shops. Sodium montmorillonite is also used as the base of some cat litter products, due to its adsorbent and clumping properties. Montmorillonite can be calcined to produce arcillite, a porous material.

This calcined clay is sold as a soil conditioner for playing fields and other soil products such as for use as bonsai soil as an alternative to akadama. Montmorillonite is effective as an adsorptive of heavy metalshowever the impact this has on human health is unknown.

Hence it will not help when ingested, as it almost certainly doesn't pass through the intestinal mucous membranes. For external use, montmorillonite has been used to treat contact dermatitis.

Montmorillonite clay is added to some dog and cat foods as an anti-caking agent and because it may provide some resistance to environmental toxins, though research on the subject is not yet conclusive.Far infrared therapy can be combined with external clay therapy with excellent results.

What is Bentonite? Bentonite is a name given to a particular clay that was originally found in Fort Benton, Eastern Wyoming. The name was given by W. Knight in Previously, it was called Taylorite, which was named after William Taylor, who first began to draw attention to the clay deposits.

Geologists often describe bentonite as a clay mineral containing Montmorillonite, which poses a rather curious problem, as Montmorillonite is a name of a particular clay that was discovered in Montmorillon, France, named by Mauduyt in MacEwan suggested the term montmorillonoid for the group name to avoid confusion with montmorillonite as a specific mineral name, and Correns suggested Montmorin as the group name.

Neither of these names has found favor. The name smectite suggested as a group name by the Clay Minerals Group of the Mineralogical Society of Great Britain at the outset met strong opposition, particulary by many American mineralogists, but it is becoming widely accepted. Montmorillonites are three-layer minerals consisting of two tetrahedral layers sandwiched around a central octahedral layer Figure 1. Oxide anions at the apices of the tetrahedral subunits are directed inward where they surround interior aluminum, iron and magnesium cations, thereby forming the octahedral subunits of the octahedral layer.

Bonding, between the shared interior oxide anions and the cations in both the tetrahedral and the octahedral layers, links the layers together and yields the unique sheet structure characteristic of clay minerals. This slight excess negative charge on the sheets is counterbalanced by free-moving exchangeable cations which exist between them. These three layers in each sheet comprise individual bentonite platelets which are typically 1 nm in thickness and 0, microns in diameter.

Dry platelets of sodium bentonite are most commonly grouped together in a face-to-face arrangement, with exchangeable cations and small amounts of adsorbed wares in an interlayer region between each platelet. The thickness of the interlayer region is variable depending on the amount of water adsorbed between the platelets. If the terms bentonite and montmorillonite had both been coined late in the 20th Century, then it's possible that one would be saying that " Sodium montmorillonite is the name for the ore whose major constituent is the clay mineral, sodium bentonite.

To fully illustrate this, consider the following classification made by American Colloid, one of the premiere Bentonite mining organizations in the United States:. Bentonite - HPM20 : "High-purity, air-classified sodium bentonite, selectively-mined, consisting of micronized particles and supplied as a free-flowing powder.Diosmectite brand names SmectaSmecdral is a natural silicate of Aluminium and magnesium used as an intestinal adsorbent in the treatment of several gastrointestinal diseasesincluding infectious and non-infectious acute and functional chronic Diarrheaincluding irritable bowel syndrome diarrhea subtype.

Other uses include: chronic diarrhea caused by radiation-induced, chemotherapy-induced, and acquired immune deficiency syndrome-associated chronic diarrhea. The use of Diosmectite as an adjuvant to rehydration therapy for acute infectious functional diarrhea in children may reduce the duration of diarrhea by starting its use from day one; it increases cure rate by third day; and may reduce stool output but has no effect on hospitalization rates or need for intravenous therapy.

Its effectiveness in improving stool consistency is the result of its ability to absorb bacteria, viruses and toxins as well as strengthening the intestinal mucus barrier to reduce luminal antigens passing through the mucus barrier which in turn helps to reduce inflammation. From Wikipedia, the free encyclopedia. Redirected from Magnesium aluminum silicate. Diosmectite Diosmectite powder. Intest Res. Cochrane Database of Systematic Reviews. December Digestive and Liver Disease.

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Antidiarrhealsintestinal anti-inflammatory and anti-infective agents A Oral rehydration therapy. Saccharomyces boulardii. Albumin tannate Ceratonia Crofelemer Octreotide Racecadotril. Categories : Digestive system Medicinal clay Gastrointestinal system drug stubs. Namespaces Article Talk. Views Read Edit View history. Help Learn to edit Community portal Recent changes Upload file. Download as PDF Printable version. Diosmectite powder. International Drug Names.

This drug article relating to the gastrointestinal system is a stub. You can help Wikipedia by expanding it.Clay minerals are hydrous aluminium phyllosilicatessometimes with variable amounts of ironmagnesiumalkali metalsalkaline earthsand other cations found on or near some planetary surfaces. Clay minerals form in the presence of water [1] and have been important to life, and many theories of abiogenesis involve them.

smectite wiki

They are important constituents of soilsand have been useful to humans since ancient times in agriculture and manufacturing. Clays form flat hexagonal sheets similar to the micas. Clay minerals are common weathering products including weathering of feldspar and low-temperature hydrothermal alteration products. Clay minerals are very common in soils, in fine-grained sedimentary rocks such as shalemudstoneand siltstone and in fine-grained metamorphic slate and phyllite.

Clay minerals are usually but not necessarily ultrafine-grained normally considered to be less than 2 micrometres in size on standard particle size classifications and so may require special analytical techniques for their identification and study.

These methods can be augmented by polarized light microscopya traditional technique establishing fundamental occurrences or petrologic relationships.

Given the requirement of water, clay minerals are relatively rare in the Solar Systemthough they occur extensively on Earth where water has interacted with other minerals and organic matter.

Clay minerals have been detected at several locations on Mars[2] including Echus ChasmaMawrth Vallisthe Memnonia quadrangle and the Elysium quadrangle. Spectrography has confirmed their presence on asteroids including the dwarf planet Ceres [3] and Tempel 1 [4] as well as Jupiter's moon Europa. Clay minerals can be classified as orthis originates because they are fundamentally built of tetrahedral silicate sheets and octahedral hydroxide sheets, as described in the structure section below.

A clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite. A clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talcvermiculiteand montmorillonite.

Mixed blue layer clay variations exist for most of the above groups. Ordering is described as a random or regular order and is further described by the term reichweitewhich is German for range or reach.

Montmorillonite

Literature articles will refer to an R1 ordered illite-smectite, for example. This type would be ordered in an ISIS fashion. R0 on the other hand describes random ordering, and other advanced ordering types are also found R3, etc. Mixed layer clay minerals which are perfect R1 types often get their own names.

R1 ordered chlorite-smectite is known as corrensite, R1 illite-smectite is rectorite. The crystallographic structure of clay minerals became better understood in the s with advancements in the x-ray diffraction XRD technique indispensable to decipher their crystal lattice. The sheet units have the chemical composition Al, Si 3 O 4.All Minerals.

A highly plastic clay mineral related to montmorillonite bentonitemore correctly, the name of the group on minerals that includes montmorillonite and other similar minerals. The following was obtained from Southern Clay Minerals: Smectite is a platy clay mineral. Three properties make smectite unique: Shape - Smectite is a very lamellar material. Individual platelets resemble a business card in terms of morphology. Size - Naturally occurring smectite ranges in size from 0.

Charge - Smectite platelets have a negative ionic charge within the body of the platelet and a positive charge on the edge of the platelet. Due to its particular combination of properties, smectite can provide a host of benefits in water-based coatings. Due to its ability to structure in aqueous media, it is a thickener in low to mid shear ranges. Oftentimes it can be used to reduce or replace in combination with other thickeners cellulosic thickeners.

It also prevents settling and syneresis phase separation. Smectite will act as a pigment spacer U. Patent 5, to improve hiding in titanium dioxide pigmented systems. Smectite improves sag resistance while not affecting flow and leveling to the extent other mineral thickeners might. This is due to smectite's true thixotropy which affords a delay in the recovery of viscosity when shear is released as opposed to the pseudoplastic tendencies of other minerals which cause an immediate recovery of viscosity.

By Tony Hansen. Southern Clay Products, Inc. Porcelain Standard porcelains used by potters and for the production of sanitary and table ware have surprisingly similar recipes. But their plasticities vary widely. Clay What is clay?

How is it different that regular dirt? For ceramics, the answer lies on the microscopic level with the particle shape, size and how the surfaces interact with water.

Montmorillonite, Bentonite. Clay Minerals The property of plasticity is evident in a wide array of materials of different mineralogy. In addition, many minerals are considered parent minerals to clays, they weather down to become these clays.Clay minerals are hydrous aluminium phyllosilicatessometimes with variable amounts of ironmagnesiumalkali metalsalkaline earthsand other cations found on or near some planetary surfaces. Clay minerals form in the presence of water [1] and have been important to life, and many theories of abiogenesis involve them.

They are important constituents of soilsand have been useful to humans since ancient times in agriculture and manufacturing. Clays form flat hexagonal sheets similar to the micas. Clay minerals are common weathering products including weathering of feldspar and low-temperature hydrothermal alteration products. Clay minerals are very common in soils, in fine-grained sedimentary rocks such as shalemudstoneand siltstone and in fine-grained metamorphic slate and phyllite.

Clay minerals are usually but not necessarily ultrafine-grained normally considered to be less than 2 micrometres in size on standard particle size classifications and so may require special analytical techniques for their identification and study. These methods can be augmented by polarized light microscopya traditional technique establishing fundamental occurrences or petrologic relationships.

Clay mineral

Given the requirement of water, clay minerals are relatively rare in the Solar Systemthough they occur extensively on Earth where water has interacted with other minerals and organic matter.

Clay minerals have been detected at several locations on Mars[2] including Echus ChasmaMawrth Vallisthe Memnonia quadrangle and the Elysium quadrangle. Spectrography has confirmed their presence on asteroids including the dwarf planet Ceres [3] and Tempel 1 [4] as well as Jupiter's moon Europa. Clay minerals can be classified as orthis originates because they are fundamentally built of tetrahedral silicate sheets and octahedral hydroxide sheets, as described in the structure section below.

A clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite. A clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talcvermiculiteand montmorillonite.

Mixed blue layer clay variations exist for most of the above groups. Ordering is described as a random or regular order and is further described by the term reichweitewhich is German for range or reach. Literature articles will refer to an R1 ordered illite-smectite, for example.

This type would be ordered in an ISIS fashion. R0 on the other hand describes random ordering, and other advanced ordering types are also found R3, etc. Mixed layer clay minerals which are perfect R1 types often get their own names.

R1 ordered chlorite-smectite is known as corrensite, R1 illite-smectite is rectorite. The crystallographic structure of clay minerals became better understood in the s with advancements in the x-ray diffraction XRD technique indispensable to decipher their crystal lattice. The sheet units have the chemical composition Al, Si 3 O 4. Each silica tetrahedron shares 3 of its vertex oxygen atoms with other tetrahedra forming a hexagonal array in two-dimensions.

The fourth vertex is not shared with another tetrahedron and all of the tetrahedra "point" in the same direction; i. In clays, the tetrahedral sheets are always bonded to octahedral sheets formed from small cations, such as aluminum or magnesium, and coordinated by six oxygen atoms. The unshared vertex from the tetrahedral sheet also forms part of one side of the octahedral sheet, but an additional oxygen atom is located above the gap in the tetrahedral sheet at the center of the six tetrahedra.

This oxygen atom is bonded to a hydrogen atom forming an OH group in the clay structure. Clays can be categorized depending on the way that tetrahedral and octahedral sheets are packaged into layers. If there is only one tetrahedral and one octahedral group in each layer the clay is known as a clay.

The alternative, known as a clay, has two tetrahedral sheets with the unshared vertex of each sheet pointing towards each other and forming each side of the octahedral sheet. Bonding between the tetrahedral and octahedral sheets requires that the tetrahedral sheet becomes corrugated or twisted, causing ditrigonal distortion to the hexagonal array, and the octahedral sheet is flattened. This minimizes the overall bond-valence distortions of the crystallite. Depending on the composition of the tetrahedral and octahedral sheets, the layer will have no charge or will have a net negative charge.Covid has significantly affected our fundraising.

Please help! Learning Center What is a mineral? Mineral Name:. Locality Name:. Keyword s :. Smectite Group This page is currently not sponsored. Click here to sponsor this page. Photos of Smectite Group Saponite Karadag Reserve, Crimea, Russia. Hide all sections Show all sections. This section is currently hidden.

Click the show button to view. Formula: A 0. Monoclinic clay-like minerals. Generally for natural samples, the d spacing is approximately The group is further divided into subgroups that are either trioctahedral according to Bailey,this subgroup name is "saponite" or dioctahedral subgroup name of "montmorillonite", according to Bailey,and these subgroups are further divided into mineral species.

Prior to circathe smectite group was called the montmorillonite-saponite group. Smectite and vermiculite minerals are often referred to as "swelling" or "expandable" clay minerals. Smectite is commonly a primary constituent of bentonite see bentonite for respective genesis information and pelitic sediments e. Positive identification of minerals in the smectite group may need data from dehydration experiments thermogravimetric analysis, TGA, or differential thermo-analysis, DTAand X-ray powder patterns before and after treatment by heating and with organic liquids.


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