Hydroxides silicate glasses

The alkali metal hydroxides are also readily absorb CO2 and H2S to form carbonates (or hydrogencarbonates) and sulfides (or hydrogen-sulfides), and are extensively used to remove mercaptans from petroleum products. Amphoteric oxides such as those of Al, Zn, Sn and Pb react with MOH to form aluminates, zincates, stannates and plumbates, and even SiC>2 (and silicate glasses) are attacked. 

This describes the specific curing behavior of fly ash, cement dusts, and certain steel works byproducts, is based on the reaction of silicate and aluminous materials with quick lime. Here too, as with the above-mentioned additives, a higher pH causes the precipitation of metal hydroxides and carbonates. The British SEALOSAFE-Process uses fly-ash plus Portland cement, or alkali silicate glass and Fe/Al hydroxides to solidify a broad spectrum of wastes. In the POZ-O-TEC-Process, the wastes from flue gas scrubbers are solidified together with grate ash and fly-ash. The pozzolanic processes have the advantage of excellent longterm stability however, the products solidify rather slowly and are susceptible to acids. 

Amorphons or poorly crystallized silica contained in aggregate reacts with sodium or potassium hydroxide in aqneons solntion, and, as it is commonly known, in concrete pore solution, a significant amonnt of these hydroxides can be present. To this reactive silica belong the most freqnently opal, tridymite with defected stractnre [77] or siliceous glass. The two-stage process occurs the first stage is the typical acid-base reaction, in which the acidic silanol groups react with sodium or potassium hydroxide ... 

Metakaolin reacts with lime to yield calcium silicate hydrate. Metakaolin may also be activated by other materials such as alkali metal hydroxides, water glass, etc. Activation leads to a polycondensation product with cementing properties. The t5q)e of MK, composition, temperature at which it is produced, surface area, etc., determine the strength development characteristics of the product. In conduction calorimetry, an exothermic peak results by the reaction of MK and the activator. A strong as5mimetric peak in calorimetry is associated with an amorphous inorganic... 

Hydrogen fluoride reacts witlr metal carbonates, oxides, and hydroxides. Accumulation of these fluoride compounds can render valves and other close-fitting moving parts inoperable in a process system, causing possible equipment or process failures. Hydrogen fluoride also attacks glass, silicate ceramics, leather, natural rubber, and wood, but does not promote their combustion. 

Some metals that are chemically combined with oxygen (metal oxides) also dissolve in sodium hydroxide. For example, aluminum ore (known as bauxite) is treated with sodium hydroxide to isolate pure aluminum oxide, from which pure aluminum is obtained. Sand (silicon dioxide) will also dissolve in sodium hydroxide to form a chemical known as sodium silicate or water glass. 

Rubidium hydroxide, 27 821-822 Rubidium iodide, 27 823 Rubidium metal alloys, 27 816 Rubidium metal, pure, 27 818 Rubidium oxides, 27 816, 823 Rubidium ozonide, 78 417 Rubidium silicates, 22 452 Rubidium sulfate, 27 821 Rubidium superoxide, 78 417 Rubidium tetrahydroborate physical properties of, 4 194t Ruby, 2 405 color, 7 329 Ruby glass, 7 344... 

In 1992, R.M. Laine (University of Michigan, Ann Arbor) announced the development of a process that transforms sand and other forms of silica into reactive silicates that can be used to synthesize unusual silicon-based chemicals, polymers, glasses, and ceramics. The Lame procedure produces pentacoordinate silicates directly from low-cost raw materials—silicon dioxide,ethylene glycol, and an alkali base. The mixture is approximately a 60 1 ratio of silica gel, fused silica (or sand) to metal hydroxide and ethylene... 

Metal ions that diffuse to the surface react with atmospheric gases to form hydroxides in a thin layer of high pH [36]. Fowkes improved adhesion of a basic polymer to glass with an acid wash [6, 7] a similar treatment also improved adhesion to epoxy [37], an acidic polymer. The former effect was attributed to replacement of sodium silicate with silanols by ion exchange the latter may result from removing a corrosive layer of metal hydroxides from the interface. IGC and PTD measurements in this study demonstrate a measurable basicity on bare fibers, which other investigators also noted [6,14,17],... 

Water glass. A familiar and useful silicate is that known as water glass. Although the commercial product consists of a rather complex mixture of silicates, water glass is commonly represented by the formula for the normal sodium salt of metasilicic acid, Na2Si03. This material is produced by heating sand with sodium hydroxide under pressure... 

Inorganics Oxides (glass, MgO, Si02, A1203) Hydroxides (Al(OH)3) Salts (CaC03, BaS04, CaS04, phosphates) Silicates (talc, mica, kaolin, woolastonite) Metals (boron, steel fibers)... 

Sodium silicate is stored and shipped as a liquid, but when exposed to air, it will turn into a hard, glass-like material. In reality, it is a glass in a totally anhydrous form the sodium hydroxide content is 34% by weight, and the remaining 66% is silicon dioxide. These proportions are theoretical, however, as an anhydrous sodium silicate is not really possible because it would always be absorbing water from the air. 

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