Aluminum complexes silicates

This form of internal softening is not recommended in higher heat-flux boilers, however, because the risk of complex silicate scales is inevitable. The risk of such scales is further increased by the presence of either iron or aluminum, and analcite, acmite, or similar minerals may result. Under... 

Minerals belonging to the category of insoluble oxide and silicate minerals are many in number. Insoluble oxide minerals include those superficially oxidized and those of oxide type. The former category comprises mainly superficially oxidized sulfide minerals, including metals such as aluminum, tin, manganese, and iron which are won from their oxidic sources. As far as silicate minerals are concerned, there can be a ready reference to several metals such as beryllium, lithium, titanium, zirconium, and niobium which are known for their occurrence as (or are associated with) complex silicates in relatively low-grade deposits. 

Green earth, best known by the Italian name terra verte, is probably the main green pigment not derived from copper. Terra verte is a mixture of two minerals, caledonite and glauconite, both complex silicates of aluminum, calcium, iron, magnesium, and potassium silicate (Grissom 1986). 

The mineral zunyite, AluSisC oCOEOigCl, may be described as an example of a complex silicate.89 Of the thirteen aluminum ions twelve show octahedral coordination, the twelve octahedra forming the group... 

The mineral bauxite (A1HO,. Al(OH)s) is our main source of aluminum. Bui aluminum is also found in nature as oxide and in many complex silicates. Clay, for instance, is an aluminum silicate. 

HORNBLENDE. The mineral hornblende is a complex silicate. It is probably an isoinorphous mixture of three molecules, a calcium-iron-magnesium silicate, an aluminum-irou-magnesium silicate and an iron-magnesium silicate. A general formula ts... 

It appears that the reaction mixture must have a pH of 11 0.2 or higher for the faujasite structure to crystallize, which seems to be owing to the state of the silicate in solution. Therefore, a complexing agent for this application should provide a favorable equilibrium between its aluminum complex and hydroxoaluminate at a pH of 11 or higher. 

Blue Ultramarine blue pigments are sodium/aluminum sulfide-silicate complexes. They are used in PP and HOPE, but they have poor resistance to acidic and alkaline outdoor environments. "Cobalt blue" (cobalt aluminate) is a higher-cost, more weatherable alternative. Ferric ammonium ferrocyanide "iron blue" has been used in LDPE bags, for example. 

Synonyms Aluminum oxide silicate Cl 77004 Pyrophyllite Willinite DeTinition Complex Inorganic salt with 1 mole alumina, 1-3 moles silica naturally occurring forms andalusite, cyanite, sillimanite other aluminum silicate mins. incl. kaolinite, kochite, mullite, newtonite, pyrophyllite, etc. 

Definition Substance of volcanic origin consisting chiefly of complex silicates of aluminum and alkali metals... 

Aluminum is the third most abundant element in the earth s crust. Unfortunately, it is mostly present as complex silicates and clay from which extraction is uneconomic. 

Mica Complex silicate H2SO4 600, HF, starch, gum, lactic acid, Na2Si03 Lead salt R-810,825, amine, cationic collector, alkaline resin Alcohols, pine oil, cresyhc acid 25. 31 dithiophosphates Aluminum salt, polyphos[diate... 

To date, potentiometric titration is still a main approach to study the surface acid base chemistry of clay minerals. Only some papers deal with the dissolution of a solid matrix resulting in various hydrolyzed aluminum species, silicic acid and their product hydrous aluminosilicates, though their interaction with a clay surface should be considered in the modeling description. The surface complexation model (SCM) was successfully applied in a recent paper [6] to interpret surface acid-base reactions involving the dissolution of illite clays during prolonged titration. Voluminous literature on ion adsorption and surface complexation... 

At near-neutral pH, aluminum is preferentially complexed by hydroxide, total aluminum solubility is very low, and organic-aluminum complexes are not favored. At this pH, however, organic-silica complexes are more favored, silica is mobilized, and silicate and quartz dissolution rate is accelerated. Organic-acid concentration, however, must be much higher than for the equivalent mobilization of aluminum because of the weaker silica -organic-acid interaction. In a near-neutral pH, organic-rich system, silica is mobilized from the silicate surface with the released aluminum unstable with... 

High aluminum concentrations in carboxylic acid/silicate dissolution experiments have been interpreted in terms of formation of organic anion-aluminum complexes (Surdam et al. 1984 Surdam and MacGowan 1987 ... 

Aluminosilicates are also likely to form by condensation of silicate and aluminale complexes. Silicates can react with many elements, and with aluminum as the aluminate ion [Al(OH)4] in particular. The aluminate ion has a very low propensity towards condensation but it can be incoiporatcd easily in polysilicates silicates... 

After oxygen, silicon is the most plentiful element in the lithosphere. In forms ranging from pure silica to complex silicates, it predominates in the solid phase of most soils, and dissolved silica is frequently a principal component of soil solution. In view of its abundance in the earth s crust, it is perhaps surprising that relatively little attention has been paid to its function in soil and its influence on soil properties. The less abundant elements—iron and aluminum—have engendered, by comparison, much more interest and investigation, possibly because of the importance of their role in the chemistry of soil phosphorus. 

Paints are complex formulations of polymeric binders with additives including anti-corrosion pigments, colors, plasticizers, ultraviolet absorbers, flame-retardant chemicals, etc. Almost all binders are organic materials such as resins based on epoxy, polyurethanes, alkyds, esters, chlorinated rubber and acrylics. The common inorganic binder is the silicate used in inorganic zinc silicate primer for steel. Specific formulations are available for application to aluminum and for galvanized steel substrates. 

More complex (and more common) structures result when some of the sili-con(IV) in silicates is replaced by aluminum(III) to form the aluminosilicates. The missing positive charge is made up by extra cations. These cations account for the difference in properties between the silicate talc and the aluminosilicate mica. One form of mica is KMg (Si1AlO10)(OH)2. In this mineral, the sheets of tetrahedra are held together by extra K+ ions. Although it cleaves neatly into transparent layers when the sheets are torn apart, mica is not slippery like talc (Fig. 14.40). Sheets of mica are used for windows in furnaces. 

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