Hydrous aluminum silicate

Aluminum silicate dihydrate Aluminum silicate hydrated Aluminum silicate hydrous Aluminum silicate hydroxide. See Kaolin Aluminum sodium silicate. See Sodium silicoaluminate... 

Clay. This material is found at the surface of the earth and often is the major component of soils. The material is plastic when wetted, but becomes hard and brittle when dried and heated. It is composed mainly of hydrous aluminum silicates as well as other minerals. 

Shale. This sedimentary rock is formed by the consolidation of clay, mud and silt. It contains substantial amounts of hydrous aluminum silicates. 

Bentonite is the name for a hydrous aluminum silicate comprised principally of the clay mineral montmorillonite, notable for its ability to swell in water and to form a very low-permeability seal." It is available as powder, granule (chip), or pellets. Powder and granule sizes are produced by processing after mining. Bentonite powder... 

Turquoise Hydrous copper aluminum silicate Light blue... 

Zeolite minerals are hydrous-aluminum-silicates whose general chemical formula can be expressed as... 

ANALCIME. A common zeolite mineral, NaAlSi2C>6 H20, a hydrous soda-aluminum silicate. It crystallizes in the isometric system, hairiness, 5-5.5 specific gravity, 2.2. vitreous luster colorless to white but may be grayish, greenish, yellowish, or reddish. Its trapezohedral crystal resembles garnet but is softer it is distinguished from lcucitc only by chemical tests. 

The natural clay minerals are hydrous aluminum silicates with iron or magnesium replacing aluminum wholly or in part, and with alkali or alkaline earth metals present as essential constituents in some others. Their acidic properties and natural abundance have favored their use as catalysts for cracking of heavy petroleum fractions. With the exception of zeolites and some specially treated mixed oxides for which superacid properties have been claimed, the acidity as measured by the color changes of absorbed Hammett bases is generally far below the superacidity range. They are inactive for alkane isomerization and cracking below 100 °C and need co-acids to reach superacidity. 

The 1 1 clay-mineral type consists of one tetrahedral sheet and one octahedral sheet. These two sheets are approximately 7 A thick. This two-sheet type is divided into kaolinite (dioctahedral) and serpentine (trioctahedral) groups. The kaolinite minerals are all pure hydrous aluminum silicates. The different members are characterized by the manner of stacking of the basic 7 A layers (Brindley, 1961b). 

The three-sheet or 2 1 layer lattice silicates consist of two silica tetrahedral sheets between which is an octahedral sheet. These three sheets form a layer approximately 10 A thick. The oxygens at the tips of the tetrahedra point towards the center octahedral sheet and substitute for two-thirds of the octahedrally coordinated hydroxyls. The 2 1 clay minerals include the mica and smectite groups which are by far the most abundant of the clay minerals. The pure end members of this type are talc, a hydrous magnesium silicate pyrophyllite, a hydrous aluminum silicate and minnesotaite, a hydrous iron silicate. 

The two layer silicates are divided into the kaolinite (dioctahedral) and serpentine (trioctahedral) subgroups. The dioctahedral minerals are hydrous aluminum silicates containing minor amounts of other constituents. The trioctahedral minerals vary widely in composition and isomorphous substitution is common however, these minerals are relatively rare and chemical data are limited. 

Clay mineral attapulgite is an acicular-shaped hydrous magnesium aluminum silicate. Large deposits occur in South Georgia and North Florida. It is receiving increasing use in partial replacement of furafil. 

Isomorphic substitution is especially significant in the case of clay minerals (hydrous aluminum silicates), which are formed by the weathering of the primary silicates of igneous rocks. Most of the clay minerals belong to the phyllosilicates, but there are some that are of fibrous and amorphous structure. 

Clays were probably the first ceramic raw materials. Clay minerals are fine-particle hydrous aluminum silicates, like those shown in Figure... 

Is the trade name for pyrophyllite, a hydrous aluminum silicate. This mineral is chemically a clay but has the appearance and some of the physical properties of talc. The principal use is as a diluent or carrier for agricultural toxicants, PYRAX is also used in water paints, dry wall plasters and as a filler for plastics. 

The USP 28 describes kaolin as a native hydrated aluminum silicate, powdered and freed from gritty particles by elutriation. The BP 2004 similarly describes light kaolin but additionally states that it contains a suitable dispersing agent. Light kaolin (natural) BP contains no dispersing agent. Heavy kaolin is described in the BP 2004 and PhEur 2005 as a purified, natural hydrated aluminum silicate of variable composition. The JP 2001 describes kaolin as a native hydrous aluminum silicate. 

Names attapulgite. hydrous magnesium aluminum silicate. Fuller s earth, palygorskite, clay... 

ASP072,101,102,170,200,400P, 600,602,672, NC, Buca, Catalpo - hydrous aluminum silicate, spray-dried or highly pulverized powders. ASP 101 is stearate coated and ASP NC is delaminated Santitone 5, 5HB, Special, SP-33, Whitetex - calcinated kaolins... 

Muscovite Mica 6915,6912,6908,6905 - grades of different particles sizes for plastics and coatings SG-70, SG-90 - hydrous potassium aluminum silicate produced by patented process which gives high brightness delaminated muscovite mica for joint compounds, adhesives, sealants, coatings... 

The clays and micas are compositionally complex hydrous aluminum silicates. Structurally they are called phyllosilicates, from the Greek word phyllon, or leaf. The phyllosilicates are continuous sheet... 

In basalts, lawsonite is the only hydrous phase which is stable in the deep mantle and this phase dehydrates at the depth of the mantle transition zone. Similarly in subducted pelagic sediments there is a series of hydrated aluminum silicates and oxides (including the phase Egg - AlSiOs.OH) which also remain stable down to transition zone depths (Williams Hemley, 2001). 

It is well known that organic complex-formers, such as simple organic acids (citric, oxalic, tartaric, salicyclic) formed by microorganisms in soils and humic or fulvic acids, solubilize mineral iron(III) and aluminum. These complex-formers not only increase the solubility of these minerals but also are able to form chelates on hydrous oxide surfaces and thus, in turn, catalyze the dissolution of oxides and aluminum silicates (Kummert and Stumm, 1980 Sigg and Stumm, 1980). The downward vertical displacement of A1 and Fe, as it is observed in the podsolization of soils, can be accounted for by considering the effect of pH and of complex formers on both solubility equilibria and dissolution rates (Schnoor and Stumm, 1985 Schnoor and Stumm, 1986). 

Chelate A dissolved species, typically organic, with two or more funcHonal groups that are capable of sharing pairs of electrons with a metal caHon Clastic Material composed of pieces of pre-exisHng rocks Clay Rock or mineral with a grain size less than 4 fim (for geologists 2 /am for soil scientists), often consisHng of hydrous aluminum silicates... 

ASP . [Engelh ] Hydrous aluminum silicates extender pigment in paints, inks filler irovidii i acity in plastics in adhesives for corrugated board, laminated fiiber board, paper bag seams in rubber industry, in masdes, putties, caulks, textile and chemical conditioning. 

B-80. n le Kaolin] Hydrous aluminum silicate-kaolin used in inks, plastics, paint adhesives, and pharmaceutical i lks. 

Buca . [Engelhard] Hydrous aluminum silicate reinforcing extender for rubber and polymer systems. 

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