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Carbone monoxide Volume

Carbon monoxide volume mixing ratio (ppm) qC02... [Pg.38]

Because the synthesis reactions are exothermic with a net decrease in molar volume, equiUbrium conversions of the carbon oxides to methanol by reactions 1 and 2 are favored by high pressure and low temperature, as shown for the indicated reformed natural gas composition in Figure 1. The mechanism of methanol synthesis on the copper—zinc—alumina catalyst was elucidated as recentiy as 1990 (7). For a pure H2—CO mixture, carbon monoxide is adsorbed on the copper surface where it is hydrogenated to methanol. When CO2 is added to the reacting mixture, the copper surface becomes partially covered by adsorbed oxygen by the reaction C02 CO + O (ads). This results in a change in mechanism where CO reacts with the adsorbed oxygen to form CO2, which becomes the primary source of carbon for methanol. [Pg.275]

Semiconductors. Phosphine is commonly used in the electronics industry as an -type dopant for siUcon semiconductors (6), and to a lesser extent for the preparation of gaUium—indium—phosphide devices (7). For these end uses, high purity, electronic-grade phosphine is required normally >99.999% pure. The main impurities that occur in phosphine manufactured by the acid process are nitrogen [7727-37-9] hydrogen [1333-74-0] arsine [7784-42-17, carbon dioxide [124-38-9], oxygen [7782-44-7], methane [74-82-8], carbon monoxide [630-08-0], and water [7732-42-1]. Phosphine is purified by distillation under pressure to reduce the level of these compounds to <1 ppm by volume. The final product is sold as CYPURE (Cytec Canada Inc.) phosphine. [Pg.318]

The usual precautions must be observed around the high tension electrical equipment supplying power. The carbon monoxide formed, if collected in closed furnaces, is usually handled through blowers, scmbbers, and thence to a pipe transmission system. As calcium carbide exposed to water readily generates acetylene, the numerous cooling sections required must be constandy monitored for leaks. When acetylene is generated, proper precautions must be taken because of explosibiUty of air—acetylene mixtures over a wide range of concentrations (from 2.5 to 82% acetylene by volume) and the dammabiUty of 82—100% mixtures under certain conditions. [Pg.462]

In one patent (31), a filtered, heated mixture of air, methane, and ammonia ia a volume ratio of 5 1 1 was passed over a 90% platinum—10% rhodium gauze catalyst at 200 kPa (2 atm). The unreacted ammonia was absorbed from the off-gas ia a phosphate solution that was subsequently stripped and refined to 90% ammonia—10% water and recycled to the converter. The yield of hydrogen cyanide from ammonia was about 80%. On the basis of these data, the converter off-gas mol % composition can be estimated nitrogen, 49.9% water, 21.7% hydrogen, 13.5% hydrogen cyanide, 8.1% carbon monoxide, 3.7% carbon dioxide, 0.2% methane, 0.6% and ammonia, 2.3%. [Pg.377]

The amount of oxygen in the combustion gas is regulated by controlling the ratio of air to fuel in the primary section. As previously mentioned, the ideal volumetric ratio of air to methane is 10 1. If less than 10 volumes of air are used with one volume of methane, the combustion gas will contain carbon monoxide. The reaction is as follows ... [Pg.375]

Asphyxiant Simple asphyxiants are inert gases which deplete the oxygen supply in the breathing air to below the critical value of J8% by volume, such as gaseous fuels or nitrogen. Chemical asphyxiants, such as carbon monoxide and hydrogen cyanide, have a direct biological effect. [Pg.1415]

Carbon monoxide (CO) is a colurless, odorless, and tasteless gas. Inhalation of as little as 0.3 percent by volume can cause death within thirty minutes. The exhaust gas from spark ignition engines at an idle speed has a high CO content. For this reason NEVER allow an engine to run in an enclosed space such as a closed garage. [Pg.334]

Even below the condensation pressure the pressure-volume product was not perfectly constant. With measurements of sufficient accuracy and precision, we can see that the PV product of ammonia at 25°C is not really constant after all. It varies systematically from 24.45 at 0.1000 atmospheres to 23.10 at 9.800 atmospheres, just before condensation begins. Similar measurements on 28.0 grams of carbon monoxide at 0°C show that the PV product is 22.410 at 0.2500 atmospheres pressure, but if the pressure is raised to 4.000 atmospheres, the PV prod-uci becomes 22.308. This type of deviation is common. Careful measurements reveal the fact that no gas follows perfectly the generalization PV = a constant at all pressures. On the other hand, every gas follows this rule approximately, and the fit becomes better and better as the pressure is lowered. So we find that every gas approaches the behavior PV = a constant as pressure is lowered. [Pg.60]

Carbon monoxide (CO) is a colorless and odorless gas molecule. This inorganic compound, at standard temperature and pressure, is chemically stable with low solubility in water but high solubility in alcohol and benzene. Incomplete oxidation of carbon in combustion is the major source of environmental production of CO. When it burns, CO yields a violet flame. The specific gravity of CO is 0.96716 with a boiling point of -190°C and a solidification point of-207°C. The specific volume of CO is 13.8 cu ft/lb (70°F). [Pg.321]

Carbon Monoxide Boilers Carbon monoxide boilers are used to recover waste heat generated from oil refining fluid catalytic cracking (FCC) processes. The FCC process produces copious volumes of by-product gas containing 5 to 8% carbon monoxide (CO), which has a heat content of about 150 Btu/lb. A 10,000 barrel (bbl) per day FCC unit produces 60,000 to 150,000 lb/hr of CO. [Pg.57]

Ethanol, CH3CH2OH, is produced from the biological fermentation of the starches in grains, mainly corn. It currently makes up about 10% by volume of gasoline in the United States, thereby reducing pollution as well as the use of petroleum. The oxygen atom in the ethanol molecule reduces emissions of carbon monoxide and hydrocarbons by helping to ensure complete combustion. One bushel of... [Pg.367]

Carbon monoxide chemisorption was used to estimate the surface area of metallic iron after reduction. The quantity of CO chemisorbed was determined [6J by taking the difference between the volumes adsorbed in two isotherms at 195 K where there had been an intervening evacuation for at least 30 min to remove the physical adsorption. Whilst aware of its arbitrariness, we have followed earlier workers [6,10,11] in assuming a stoichiometry of Fe CO = 2.1 to estimate and compare the surface areas of metallic iron in our catalysts. As a second index for this comparison we used reactive N2O adsorption, N20(g) N2(g) + O(ads), the method widely applied for supported copper [12]. However, in view of the greater reactivity of iron, measurements were made at ambient temperature and p = 20 Torr, using a static system. [Pg.259]


See other pages where Carbone monoxide Volume is mentioned: [Pg.159]    [Pg.202]    [Pg.7]    [Pg.151]    [Pg.152]    [Pg.159]    [Pg.202]    [Pg.7]    [Pg.151]    [Pg.152]    [Pg.258]    [Pg.697]    [Pg.26]    [Pg.428]    [Pg.431]    [Pg.494]    [Pg.252]    [Pg.43]    [Pg.45]    [Pg.156]    [Pg.238]    [Pg.377]    [Pg.55]    [Pg.58]    [Pg.481]    [Pg.152]    [Pg.36]    [Pg.79]    [Pg.93]    [Pg.207]    [Pg.821]    [Pg.457]    [Pg.432]    [Pg.747]    [Pg.523]    [Pg.57]    [Pg.691]    [Pg.691]    [Pg.381]    [Pg.150]    [Pg.53]    [Pg.322]   
See also in sourсe #XX -- [ Pg.2 ]




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