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Industry silicate

The first industrial siliceous cracking catalyst was an acid-leached bentonite clay to which about 1 % of manganese dioxide was added for the purpose of increasing the rate of burning of carbonaceous deposits during regeneration. Essentially the same type of catalyst, without the added manganese dioxide, is in wide use today. [Pg.5]

Heavy clay industry silicate ceramic (clay ceramic) coarse ceramic bodies 1000 80 5-150 bricks, roofing tiles, ceiling bricks, wall and floor tiles... [Pg.65]

The feasibility of the powder technology approach for obtaining layered cylindrical compacts from industrial silicate wastes, e. g. cullet glass and vitrified incinerator filter ash, was demonstrated [60], as shown in Figure 9. The materials underwent pressureless sintering after being compacted uniaxially in a die. They did not exhibit processing microcracks or other microstructural defects at the core/outer layer interfaces. [Pg.524]

In the rubber industry, silicate layer minerals represent the largest volume of filler, second to carbon black. The silicate mineral used is primarily Kaolin clay. Kaolin occurs naturally. Kaolin clays are mined, and they are subsequently pulverized and refined by air and water... [Pg.39]

The fundamental structural imit of industrial silicate minerals is the silica tetrahedron. Quartz is just a densely packed arrangement of these tetrahedra, as depicted in Figure 3. [Pg.3]

Naturally-found silicates are complex mixtures of minerals which are best characterised by XRD, TGA and DTA. Special methods of chemical analysis are available and are used in special laboratories. However, cement, which is an industrial silicate product, can be analysed more readily than natural silicates. Hie composition of cement is usually expressed as oxides of Si, Ca, Al, S, Fe(III) and Mg besides the alkali metals Na and K. [Pg.73]

The alkali silicates are soluble in water and are used industrially. See sodium silicates. [Pg.358]

Cobalt compounds have been in use for centuries, notably as pigments ( cobalt blue ) in glass and porcelain (a double silicate of cobalt and potassium) the metal itself has been produced on an industrial scale only during the twentieth century. Cobalt is relatively uncommon but widely distributed it occurs biologically in vitamin B12 (a complex of cobalt(III) in which the cobalt is bonded octahedrally to nitrogen atoms and the carbon atom of a CN group). In its ores, it is usually in combination with sulphur or arsenic, and other metals, notably copper and silver, are often present. Extraction is carried out by a process essentially similar to that used for iron, but is complicate because of the need to remove arsenic and other metals. [Pg.401]

R. WoUast, Proceedings of the 8th Conference on the Silicate Industry, Akadfimiai Kiado, Budapest, Hungary, 1966. [Pg.482]

Filter aids should have low bulk density to minimize settling and aid good distribution on a filter-medium surface that may not be horizontal. They should also be porous and capable of forming a porous cake to minimize flow resistance, and they must be chemically inert to the filtrate. These characteristics are all found in the two most popular commercial filter aids diatomaceous silica (also called diatomite, or diatomaceous earth), which is an almost pure silica prepared from deposits of diatom skeletons and expanded perhte, particles of puffed lava that are principally aluminum alkali siheate. Cellulosic fibers (ground wood pulp) are sometimes used when siliceous materials cannot be used but are much more compressible. The use of other less effective aids (e.g., carbon and gypsum) may be justified in special cases. Sometimes a combination or carbon and diatomaceous silica permits adsorption in addition to filter-aid performance. Various other materials, such as salt, fine sand, starch, and precipitated calcium carbonate, are employed in specific industries where they represent either waste material or inexpensive alternatives to conventional filter aids. [Pg.1708]

Corrosion of industrial alloys in alkaline waters is not as common or as severe as attack associated with acidic conditions. Caustic solutions produce little corrosion on steel, stainless steel, cast iron, nickel, and nickel alloys under most cooling water conditions. Ammonia produces wastage and cracking mainly on copper and copper alloys. Most other alloys are not attacked at cooling water temperatures. This is at least in part explained by inherent alloy corrosion behavior and the interaction of specific ions on the metal surface. Further, many dissolved minerals have normal pH solubility and thus deposit at faster rates when pH increases. Precipitated minerals such as phosphates, carbonates, and silicates, for example, tend to reduce corrosion on many alloys. [Pg.185]

Corrective Action Application In Massachusetts, a municipal wastewater treatment plant receives a number of wastestreams containing heavy metals from local industries. When tested, the dewatered sludge failed the EP toxicity test. In order to permit landfill disposal of the sludge, solidification processes were examined. A soluble, silicate-based system, developed by Chemfix, was ultimately selected which produced a product whose leachate passed the EP toxicity test (Sullivan, 1984). [Pg.182]

The uses in the glass and ceramics industries reflect the diagonal relation between boron and silicon and the similarity of vitreous borate and silicate networks (pp. 203, 206 and 347). In the UK and continental Europe (but not in the USA or Japan) sodium perborate (p. 206) is a major constituent of washing powders since it hydrolyses to H2O2 and acts as a bleaching agent in very hot water ( 90°C) in the USA domestic washing machines rarely operate above 70°, at which temperature perborates are ineffective as bleaches. [Pg.140]

Silicon shows a rich variety of chemical properties and it lies at the heart of much modern technology/ Indeed, it ranges from such bulk commodities as concrete, clays and ceramics, through more chemically modified systems such as soluble silicates, glasses and glazes to the recent industries based on silicone polymers and solid-state electronics devices. The refined technology of ultrapure silicon itself is perhaps the most elegant example of the close relation between chemistry and solid-state physics and has led to numerous developments such as the transistor, printed circuits and microelectronics (p. 332). [Pg.328]

The main difference between the two types are that the reaction products of the silico fluoride types are less soluble in water and are also harder, which may give better in-service performance but at a slightly higher material cost. However, with recent developments in floor-laying techniques, the concrete substrates for industrial floors are laid with much more dense low-porosity surfaces, so that neither silicate nor silico fluoride treatments are as effective as they used to be, when the concrete used had a slightly more open finish and hence was more receptive to these treatments. With modern concrete floors, it is imperative to wash any material not absorbed into the surface within a short period. Otherwise, unpleasant white alkaline deposits, which are difficult to remove, may occur. [Pg.102]

The zinc silicate, epoxy and coal tar/epoxy coatings are still used. Coal tar epoxies are used for crude oil tanks, sometimes on all the interior surfaces but more often for a) the bottom of the tank and about 2 m up the sides, b) the top of the tank and about 2 m down the sides, and (c) other horizontal surfaces where seawater ballast may lie. These partly coated tanks are frequently also fitted with cathodic protection to prevent corrosion of the uncoated areas when seawater ballast is carried. The pure epoxy or coal tar epoxy coatings applied in bulk cargo tanks used for the carriage of grain must be approved by the North of England Industrial Health Service, or by similar independent authorities in other countries. [Pg.653]

Typically, high-pressure WT boiler plants (say, over 650-900 psig) require some degree of MU water silica removal. Most commercial and general industrial facilities however, operate boiler plants at pressures below 300 psig, and irrespective of whether FT or WT boilers are employed, a silicate removal process usually is nor provided or deemed necessary. [Pg.162]

The removal of dirt and stubborn grease generally requires the use of aqueous-based, heavy-duty industrial cleaners. These cleaners may or may not contain traditional ingredients like caustic or phosphate (which can be replaced by silicates or organic surfactants). [Pg.649]

Polymer layered-silicate day nano-composites (PLCN) attracted lately major interests into the industry and academic fields, since they usually show improved properties with comparison by virgin polymers or their conventional micro and macro-composites. Improvements induded increase in strength, heat resistance (Giannelis, 1998), flammability (Gilman, 2000) and a decrease in gas permeability (Xu et ah, 2001) as well as an increase in biodegradability (Sinha et al., 2002). [Pg.31]

Over 50% is used to make glass. Other uses include the preparation of chemicals (such as sodium silicate and sodium phosphate), soaps and detergents, in the pulp and paper industry, and in water treatment. Substantial amounts are exported. [Pg.30]


See other pages where Industry silicate is mentioned: [Pg.43]    [Pg.546]    [Pg.129]    [Pg.541]    [Pg.1]    [Pg.1]    [Pg.43]    [Pg.546]    [Pg.129]    [Pg.541]    [Pg.1]    [Pg.1]    [Pg.24]    [Pg.396]    [Pg.472]    [Pg.469]    [Pg.525]    [Pg.214]    [Pg.174]    [Pg.705]    [Pg.382]    [Pg.382]    [Pg.112]    [Pg.345]    [Pg.346]    [Pg.346]    [Pg.350]    [Pg.676]    [Pg.340]    [Pg.2]    [Pg.26]    [Pg.786]    [Pg.659]    [Pg.185]   
See also in sourсe #XX -- [ Pg.503 , Pg.522 , Pg.523 ]




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