Sodium aluminum silicate

Several different possible zeolite structures may result, and if the sodium content is too high, calcium and magnesium are excluded and a hard zeolite scale of sodium-aluminum silicate preferentially forms. If only calcium is present, calcium-aluminum silicate zeolite forms, also as a hard scale. If only magnesium is present in solution, it forms the flocculant magnesium aluminate, MgAl204. 

Jade jadeite Sodium aluminum silicate Mainly green, but also... 

This group of minerals consists of three silicates a potassium-aluminum silicate, a sodium-aluminum silicate, and a calcium-aluminum silicate (KAIShOj. NaAISiiO. and CaAKSriOs) and their isontorphous mixtures. 

The silanization process has also been employed to permit tailoring, for various applications, surfaces such as kaolin clays, Wollastonite, talc, and sodium aluminum silicate with amino, epoxy, mercapto, methacryloxy and vinyl groups. 

These materials are natural or artificial sodium aluminum silicates (e.g., Na2Al2Si08), which may be considered as complex salts of orthosilicic acid (H4Si04). When hard water is allowed to flow upward through a bed of granular zeolite in a vertical vessel, reactions of the type illustrated by the following equations result ... 

In the process to produce alumina (Fig. 1), bauxite is crushed and wet ground to 100-mesh, dissolved under pressure and heated in digesters with concentrated spent caustic soda solution from a previous cycle and sufficient lime and soda ash. Sodium aluminate is formed, and the dissolved silica is precipitated as sodium aluminum silicate. The undissolved residue (red mud) is separated from the alumina solution by filtration and washing and sent to recovery. Thickeners and Kelly or drum filters are used. The filtered solution of sodium aluminate is hydrolyzed to precipitate aluminum hydroxide by cooling. The precipitate is filtered from the liquor, washed, and heated to 980°C in a rotary kiln to calcine the aluminum hydroxide. 

Two types of Na+ ISFET have been reported so far. One was an inorganic sodium-aluminum-silicate (NAS) glass ISFET, which was fabricated by the hydrolysis of a mixed solution of metal alcoholates, followed by thermal treatment (2), or by the ion implantation technique (3,4). The other type of Na+ ISFET was prepared by coating with so-called solvent polymeric membrane, such as polyvinyl chloride (PVC) membrane. 

These natural minerals are alkali aluminum silicates and have been used as molecular sieves and cation exchangers. Recently they have been used to control some organic photochemical reactions, du Pont chemists1 have prepared lithiated zeolites by treatment of sodium aluminum silicates such as zeolite 13X with LiNO,. These silicates, designated Li-X and Li-Y, can effect rearrangement of a-alkyl-deoxybenzoins top-alkylbenzophenones in nearly quantitative yield. Thus photolysis... 

Sodium Aluminosilicate occurs as a fine, white, amorphous powder, or as beads. It is a series of hydrated sodium aluminum silicates having Na20 Al203 Si02 molar ratios of approximately 1 1 13, respectively. It is insoluble in water and in alcohol and other organic solvents, but at 80° to 100°, it is partially soluble in strong acids and solutions of alkali hydroxides. 

In 1977, the German firm Hankel patented the use of synthetic zeolites as a partial replacement for phosphates. The sodium aluminum silicates as zeolites have a particular lattice structure capable of absorbing heavy metal cations through ion exchange process. The role of zeolites that were added to TPS was to soften water by rapid reaction with calcium at normal temperature [4]. 

The most widely used form of zeolites is t5 e A—which are hydrated sodium aluminum silicates of empirical formula Na20 Al203 X Si02-yH20. 

Blue and green pigments. Ultramarine blue is a complex sodium aluminum silicate and sulfide, made by calcining an intimate mixture of sodium carbonate, china clay, sulfur, and silica together with some... 

Eugster H. P. and Jones B. F. (1968) Gels composed of sodium-aluminum silicate, Lake Magadi, Kenya. Science 161, 160-163. 

AISi3C,2H33, Aluminum, tris[(tri-methylsilyl)methyl]-, 24 92 Al2Na20i4Si XH2O, Sodium aluminum silicate hydrate, 22 64, Zeolite Y, 22 64... 

N24Ni3SsC,8H,8, Nickel(II), hexakis(thio-cyariato-N )-hexakis- )x-(4H-1,2,4-tri -azole-N N )-tri-, 23 160 NaAI04Si 2.25H2O, Sodium aluminum silicate, 22 61... 

Ultramarine pigments are sodium aluminum silicates with the composition Nag[Al5Si5024] Sx (Na-rich) or Nag y[Al6.ySif +y024] Sx (Si-rich), which can have a blue, green, red or violet tone, depending upon the composition of the chromogenic Sx-group. 

The authors summarized the results of the soda reaction test as follows For the high-silica samples the reaction products were identified as nepheline and sodium aluminum silicate (3 2 4). The amount of nepheline decreased with increasing alumina content, whereas the amount of (3 2 4) compound increased. The lack of silica in the high alumina samples permits the free alumina not tied up as a sodium aluminum silicate to react with the alkali to form beta-alumina. Higher amounts of soda produce sodium aluminates. 

The 90% alumina refractory showed a sharp drop in the amount of alpha-alumina present as the temperature was increased. The depletion of alpha-alumina does not occur unless excess soda is available and the temperature is above 2000°F, or unless the amount of SiOz present is not sufficient to tie up the soda as a sodium aluminum silicate. Finally, the free alumina existent in the lower silica-containing samples is depleted by the formation of beta-alumina and alkali aluminate. 

Typical fillers carbon black, silica, lead oxide (y-radiation shields), sodium aluminum silicate, clay, mica, kaolin, carbon fiber crosslinked PS beads... 

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