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Oxygen water

Chemistry. Coal gasification iavolves the thermal decomposition of coal and the reaction of the carbon ia the coal, and other pyrolysis products with oxygen, water, and hydrogen to produce fuel gases such as methane by internal hydrogen shifts... [Pg.65]

Lead is one of the most stable of fabricated materials because of excellent corrosion resistance to air, water, and soil. An initial reaction with these elements results in the formation of protective coatings of insoluble lead compounds. For example, in the presence of oxygen, water attacks lead, but if the water contains carbonates and siUcates, protective films or tarnishes form and the corrosion becomes exceedingly slow. [Pg.33]

Gaseous and Hquid nitrogen Nitrogen, min % (mol/mol) Oxygen Water, ppm (v/v) Dew point, °C Total hydrocarbon a content... [Pg.79]

Hydrogen peroxide can be dissociated over a catalyst to produce oxygen, water, and heat. It is an energetic reaction, and contaminants can spontaneously decompose the hydrogen peroxide. Oxygen from water electrolysis is used for life support on submarines. [Pg.488]

Factors such as reaction temperature, excess of oxygen, water addition, addition of other minor reactants, eg, AlCl to promote the formation of mtile, mixing conditions inside the reactor, and many others influence the quaUty of Ti02 pigment. In general, titanium white pigments produced by the chloride process exhibit better lightness than those produced by the sulfate process. [Pg.9]

Stability. In order to have maximum effectiveness over long periods of time, an antioxidant should be stable upon exposure to heat, light, oxygen, water, etc. Many antioxidants, especially in the presence of an impurity when exposed to light and oxygen, are subject to oxidation reactions with the development of colored species. Alkylated diphenyl amines are least susceptible and the -phenylenediamine derivatives the most susceptible to direct oxidation. [Pg.246]

Ba.cteria., A wide variety of bacteria can colonize cooling systems. Spherical, rod-shaped, spiral, and filamentous forms are common. Some produce spores to survive adverse environmental conditions such as dry periods or high temperatures. Both aerobic bacteria (which thrive in oxygenated waters) and anaerobic bacteria (which are inhibited or killed by oxygen) can be found in cooling systems. [Pg.272]

Hydroxide. Freshly precipitated cerous hydroxide [15785-09-8] Ce(OH)2, is readily oxidized by air or oxygenated water, through poorly defined violet-tinged mixed valence intermediates, to the tetravalent buff colored ceric hydroxide [12014-56-17, Ce(OH)4. The precipitate, which can prove difficult to filter, is amorphous and on drying converts to hydrated ceric oxide, Ce02 2H20. This commercial material, cerium hydrate [23322-64-7] behaves essentially as a reactive cerium oxide. [Pg.367]

Molecular oxygen Water, COci, oxidized nitrogen... [Pg.2215]

The crevice geometry and normally occurring corrosion combine to produce accelerated attack in the shielded region, a so-called autocat-alytic process. Initially, corrosion in oxygenated water of near neutral pH occurs by Reactions 2.1 and 2.2 ... [Pg.13]

These reactions are shown schematically near a crevice in Fig. 2.2. Many other reactions may occur at anodes and cathodes, but Reactions 2.1 and 2.2 predominate on carbon steel, for example, in near neutral pH, oxygenated water. [Pg.13]

Oxygen concentration is held almost constant by water flow outside the crevice. Thus, a differential oxygen concentration cell is created. The oxygenated water allows Reaction 2.2 to continue outside the crevice. Regions outside the crevice become cathodic, and metal dissolution ceases there. Within the crevice. Reaction 2.1 continues (Fig. 2.3). Metal ions migrating out of the crevice react with the dissolved oxygen and water to form metal hydroxides (in the case of steel, rust is formed) as in Reactions 2.3 and 2.4 ... [Pg.14]

Figure 2.4 Crevice corrosion—initial stage in oxygenated water containing sodium chloride. (Courtesy of Mars G. Fontana and Norbert D. Greene, Corrosion Engineering, McGraw-Hill Book Company, New York City, 1967.)... Figure 2.4 Crevice corrosion—initial stage in oxygenated water containing sodium chloride. (Courtesy of Mars G. Fontana and Norbert D. Greene, Corrosion Engineering, McGraw-Hill Book Company, New York City, 1967.)...
Tubercles are mounds of corrosion product and deposit that cap localized regions of metal loss. Tubercles can choke pipes, leading to diminished flow and increased pumping costs (Fig. 3.1). Tubercles form on steel and cast iron when surfaces are exposed to oxygenated waters. Soft waters with high bicarbonate alkalinity stimulate tubercle formation, as do high concentrations of sulfate, chloride, and other aggressive anions. [Pg.37]

In oxygenated water of near neutral pH and at or slightly above room temperature, hydrous ferric oxide [FelOHla] forms on steel and cast irons. Corrosion products are orange, red, or brown and are the major constituent of rust. This layer shields the underl3dng metal surface from oxygenated water, so oxygen concentration decreases beneath the rust layer. [Pg.37]

Figur 3.2 Incipient rust layer on steel in oxygenated water. (Courtesy of National Association of Corrosion Engineers, Corrosion 91 Paper No. 84 by H. M. Herro.)... Figur 3.2 Incipient rust layer on steel in oxygenated water. (Courtesy of National Association of Corrosion Engineers, Corrosion 91 Paper No. 84 by H. M. Herro.)...
Any uncoated or untreated steel or cast iron component may be attacked if it contacts oxygenated water for a prolonged period. [Pg.43]

Certain conditions, ultimately dictated by economics, make the substitution of more resistant materials a wise choice. Stainless steels (not sensitized) of any grade or composition do not form tubercles in oxygenated water neither do brasses, cupronickels, titanium, or aluminum. However, each of these alloys may suffer other problems that would preclude their use in a specific environment. [Pg.57]

Each tubercle exhibited small clam-shell marks or growth rings (Fig. 3.30). Each ring was formed by fracture at the tubercle base during growth. Ejected internal contents rapidly deposited when contacting oxygenated waters. Tubercles were hollow (Fig. 3.31). Surfaces below the... [Pg.60]

Oxides of manganese and iron are often found deposited together. Similar conditions cause oxidation of both iron and manganese ions. Exposure to oxygenated water, chlorination, and some microbiological processes causes such oxidation. Often, a few percent chlorine is found in deposits, possibly because of associated chlorination. [Pg.72]

When a clean steel coupon is placed in oxygenated water, a rust layer will form quickly. Corrosion rates are initially high and decrease rapidly while the rust layer is forming. Once the oxide forms, rusting slows and the accumulated oxide retards diffusion. Thus, Reaction 5.2 slows. Eventually, nearly steady-state corrosion is achieved (Fig. 5.2). Hence, a minimum exposure period, empirically determined by the following equation, must be satisfied to obtain consistent corrosion-rate data for coupons exposed in cooling water systems (Figs. 5.2 and 5.3) ... [Pg.99]

The ferrous hydroxide is rapidly oxidized to ferric hydroxide in oxygenated waters (Reaction 5.5) ... [Pg.100]

Stainless steels contain 11% or more chromium. Table 5.1 lists common commercial grades and compositions of stainless steels. It is chromium that imparts the stainless character to steel. Oxygen combines with chromium and iron to form a highly adherent and protective oxide film. If the film is ruptured in certain oxidizing environments, it rapidly heals with no substantial corrosion. This film does not readily form until at least 11% chromium is dissolved in the alloy. Below 11% chromium, corrosion resistance to oxygenated water is almost the same as in unalloyed iron. [Pg.103]

Corrosion resistance of stainless steel is reduced in deaerated solutions. This behavior is opposite to the behavior of iron, low-alloy steel, and most nonferrous metals in oxygenated waters. Stainless steels exhibit very low corrosion rates in oxidizing media until the solution oxidizing power becomes great enough to breach the protective oxide locally. The solution pH alone does not control attack (see Chap. 4, Underdeposit Corrosion ). The presence of chloride and other strong depassivating chemicals deteriorates corrosion resistance. [Pg.103]

Oxygen corrosion only occurs on metal surfaces exposed to oxygenated waters. Many commonly used industrial alloys react with dissolved oxygen in water, forming a variety of oxides and hydroxides. However, alloys most seriously affected are cast irons, galvanized steel, and non-stainless steels. Attack occurs in locations where tuberculation also occurs (see Chap. 3). Often, oxygen corrosion is a precursor to tubercle development. [Pg.106]

Carbon steel heat exchangers, cast iron water boxes, screens, pump components, service water system piping, standpipes, fire protection systems, galvanized steel, engine components, and virtually all non-stainless ferrous components are subject to significant corrosion in oxygenated water. [Pg.106]

Figure 5.9 Wall of steel tank, originally V2 in. (1.3 cm) thick, that was entirely converted to oxide. It was continuedly exposed to oxygenated water mist at about 180°F (82°C). Figure 5.9 Wall of steel tank, originally V2 in. (1.3 cm) thick, that was entirely converted to oxide. It was continuedly exposed to oxygenated water mist at about 180°F (82°C).
Metal-reducing bacteria, such as those that convert ferric to ferrous ion, have been suggested as an accelerant for steel corrosion in oxygenated waters, lb date, evidence of these bacteria influencing corrosion in industrial systems is scarce. [Pg.124]

Acid producers. Corrosion usually is moderate and localized. Almost all significant attack is associated with anaerobic bacteria (facultative and obhgate), as aerobic acid-producing varieties usually reside near the top of deposits and corrosion products contacting oxygenated waters. Thus, the direct effect on corrosion at metal surfaces is limited. Additionally, although acidic products may be expected to increase corrosion rates, acidity cannot be pronounced in deposits to put it simply, the deposits and corrosion products would dissolve at sufficiently acidic pH. [Pg.136]

Dissolved oxygen, water, acid, and metal-ion concentrations can have a pronounced effect on acid corrosion. For example, copper is vigorously attacked by acetic acid at low temperatures at temperatures above boiling, no attack occurs because no dissolved oxygen is present. [Pg.163]

Computes thermodynamic properties of air, argon, carbon monoxide, carbon dioxide, hydrogen, nitrogen, oxygen, water vapor, and products of combustion for hydrocarbons. Computes all properties from any two independent properties. [Pg.293]


See other pages where Oxygen water is mentioned: [Pg.1064]    [Pg.448]    [Pg.137]    [Pg.363]    [Pg.365]    [Pg.376]    [Pg.622]    [Pg.10]    [Pg.43]    [Pg.69]    [Pg.99]    [Pg.103]    [Pg.106]    [Pg.113]    [Pg.115]    [Pg.123]    [Pg.24]    [Pg.206]    [Pg.396]   
See also in sourсe #XX -- [ Pg.527 , Pg.531 ]




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Air-water oxygen transfer

Boiler water, treatment oxygen removal

Boron oxygen/water vapor

Bottom-water oxygen

Chemical oxygen demand water quality monitoring

Coastal waters oxygen distributions

Cobalt hydroxide in electrochemical production of oxygen from water

Cobalt salts oxygen production from water

Containing water-sensitive oxygen barrier

Diffusion of Water and Oxygen

Dissolved Oxygen Modeling in Surface Waters

Dissolved oxygen cooling water

Dissolved oxygen monitoring, water

Dissolved oxygen, water quality indicator

Electrochemistry hydrogen or oxygen production from water

Electron transfer reactions oxygen production from water

FATO molecular mechanics of oxygen atom. Model water molecule

Formation water oxygen isotope fractionation

Half-cells water-oxygen

Hydrogen-oxygen reactions water formation

In oxygen production from water

Iron hydroxide in electrochemical production of oxygen from water

Iron, tris in photoproduction of oxygen from water

MICROORGANISMS IN WATER ALTER LEVELS OF DISSOLVED OXYGEN

Making oxygen from water

Manganese Water Splitting, Oxygen Atom Donor

Manganese complexes oxygen production from water

Manganese oxide catalysts, oxygen production from water

Manganese salts oxygen production from water

Manganese-catalysed oxidation of water to oxygen

Metal oxides oxygen production from water

Metalloporphyrins in oxygen production from water

Nitrogen, pure, azides for preparation removal of oxygen and water

OXYGEN Sea-water

OXYGEN Spring water

OXYGEN Well water

Oxygen - Sodium Chloride - Water

Oxygen and Hydrogen Pumping, Water Vapor Electrolysis

Oxygen and Water Permeability

Oxygen and Water Quality

Oxygen bound, exchange with bulk water

Oxygen by water

Oxygen collected over water

Oxygen collection over water

Oxygen cyclic water cleavage

Oxygen depletion water

Oxygen dissolution in water

Oxygen dissolved in sea-water

Oxygen dissolved in water

Oxygen electrochemical production from water

Oxygen enhanced water treatment

Oxygen evolution from water

Oxygen from water

Oxygen generation from water

Oxygen in fresh water

Oxygen in natural waters

Oxygen in sea-water

Oxygen in water

Oxygen in water molecule

Oxygen isotopes in water

Oxygen lake-water composition

Oxygen photoelectrochemical production from water

Oxygen photoproduction from water

Oxygen pore water profiles

Oxygen production from water

Oxygen reaeration rate constant water

Oxygen solubility in water

Oxygen surface waters

Oxygen thermochemical water/carbon dioxide

Oxygen to water

Oxygen water and

Oxygen water treatment

Oxygen water versus

Oxygen-evolving complex water oxidation

Oxygen-evolving complex water oxidation model system

Oxygen-poor water

Oxygen/water half-cell reaction

Oxygenates water tolerance

Oxygenates, properties water tolerance

Oxygenation of Water

Photosynthetic Oxidation of Water Oxygen Evolution

Phthalocyanines catalysts, oxygen production from water

Platinum oxides catalysts, oxygen production from water

Polarography hydrogen or oxygen production from water

Porphyrins catalysts, oxygen production from water

Reabsorption Lines of Oxygen and Water

Reactive oxygen species water interactions

Removing Water and Oxygen

Ruthenium oxide catalysts, oxygen production from water

Ruthenium oxide hydrogen and oxygen production from water

Singlet oxygen in surface water

The Combining Ratio of Hydrogen and Oxygen in Water

The Exchange of Other Organic Compounds containing Oxygen with Water

The Influence of Oxygen Dissolved in Water

Water and Other Oxygen-Containing Compounds

Water biological oxygen demand

Water catalysts catalytic oxygen reduction

Water chemical formula oxygen atom

Water chemical oxygen demand

Water coadsorbed oxygen

Water dissolved oxygen

Water dissolved oxygen concentration

Water dissolved oxygen, determination

Water electrochemical production of hydrogen or oxygen

Water exchange rate constants measured by oxygen-17 NMR

Water from gaseous hydrogen and oxygen

Water humus and oxygen demand

Water hydrogen-oxygen bonds

Water of oxygen

Water oxidation to oxygen

Water oxygen and hydrogen

Water oxygen atoms

Water oxygen determination

Water oxygen solubility

Water oxygenated

Water oxygenation

Water oxygenation

Water pollution biochemical oxygen demand

Water resources dissolved oxygen

Water splitting oxygen

Water, oxygenated, radiolysis

Water-Oxygen Synergy

Zinc, bis in electrochemical production of hydrogen or oxygen from water

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