Carbon monoxide consumption

Rich J. J. and King G. M. (1999) Carbon monoxide consumption and production by wetland peats. FEMS Microbiol. Ecol. 28, 215-224. 

Weller (133) passed carbon monoxide over a cobalt catalyst at synthesis conditions and found high carbon monoxide consumption during the very first moment of the treatment. The carbon monoxide consumption diminished rapidly to a much lower but steady rate. Evidently a flash carbiding of the surface occurred, followed by a slower reaction of the bulk metal. The rate of synthesis is comparable with the initial carbiding rate. Hydrogenation of the cobalt carbide proceeds faster than the carbiding (in contrast to the experiences with iron catalysts). 

This preconditioning of the catalyst is necessary to separate the chemical reactions from the catalytic ones (7). In the first few minutes, the iron surface transforms to catalytically active pyrrhotite, as shown (7) by the gradual increase in carbon monoxide consumption and corresponding increase in carbon dioxide production. The initial gaseous sulfide by-products react with the iron in the catalyst to form iron sulfides. In a previous publication (8), it was shown that lattice sulfur is a more versatile and useful carbon monoxide-sufurizing agent than molecular sulfur. The hypothesis tested was that metal sulfides with relatively weak metal-to-sulfur bonds are more effective in forming the active intermediate (9) carbonyl sulfide. 

FAS is normally characterized by growth retardation, anomalies of the head and face, and psychomotor dysfunctions. Excessive consumption of ethyl alcohol may lead to malformations of the heart, extremities, and kidneys. Since consumption of ethyl alcohol is socially acceptable and prevalent even in pregnant women, the risks associated with the use of ethyl alcohol are remarkable. However, it should be kept in mind that there are several chemical compounds in tlie occupational environment that may also cause malformations even at low doses. The oc-cupationally-important known human teratogens include methyl mercury, ethyl alcohol, PCB compounds, tobacco smoke, lead, TCDD, 2,4,5- F, carbon monoxide, nitrogen dioxide, gasoline, and fluoride. 

Transportation accounts for about one-fourth of the primary energy consumption in the United States. And unlike other sectors of the economy that can easily switch to cleaner natural gas or electricity, automobiles, trucks, nonroad vehicles, and buses are powered by internal-combustion engines burning petroleum products that produce carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. Efforts are under way to accelerate the introduction of electric, fuel-cell, and hybrid (electric and fuel) vehicles to replace sonic of these vehicles in both the retail marketplace and in commercial, government, public transit, and private fleets. These vehicles dramatically reduce harmful pollutants and reduce carbon dioxide emissions by as much as 50 percent or more compared to gasoline-powered vehicles. 

Air quality, concern about deposition of toxic chemicals, 135 Air quality in Mexico City atmospheric pollution, sources, 150r carbon monoxide standards, 156r,157/ fuel consumption in metropolitan area and Mexico, 153r,154 fuel quality, 155... 

Carbon (coke) consumption, as a fuel and as a producer of the gaseous reductant, carbon monoxide, takes place in the blast furnace. An alternative source of such carbon, along with... 

In addition to the energy savings, the new process also has substantial environmental benefits. Along with the elimination of lead and nickel gases, carbon dioxide, carbon monoxide, and nitrogen oxide emissions from combustion will decrease. The consumption of refractory (a heat-resisting... 

The consumption of power in this process is theo-etically very small, as much carbon monoxide should e liquefied in the coil in the vessel B as is volatilised lutside it (this is theoretically true when the pressure )f the gas passing through the coil is atmospheric) Towever, in practice, the necessity for power consump-lon arises from the fact that liquid nitrogen must )e continuously supplied to the vessel D in order to jrevent the temperature of the plant rising from ex-ernal infiltration of heat, which takes place in spite of he most effective lagging. 

One of the major toxicity issues in cannabis consumption relates to the fact that it is most often smoked. Cannabis and tobacco smoke, apart from having different psychoactive constituents, are actually very similar in their composition (Hoffman et ai. 1975). Cannabis smoke is mutagenic, which gives it carcinogenic potential (Nahas and Latour 1992). Although no specific reports of lung cancer or emphysema from cannabis smoke exist, it is at least as harmful as tobacco smoke, containing three times as much tar and five times as much carbon monoxide (Wu et al. 1988). Cannabis smoke inflames the airways and reduces respiratory capacity. Airway obstruction and squamous metaplasias may also occur. 

The increase in efficiency between the first- and second-generation reactors was attributed to less water in the feed and lower operating temperatures. Reactor models indicated that the major source of heat loss was by thermal conduction. The selective methanation reactor lowered the carbon monoxide levels to below 100 ppm, but at the cost of some efficiency. The lower efficiency was attributed to slightly higher operating temperatures and to hydrogen consumption by the methanation process. Typical methane levels in the product stream were 5-6.2%. ... 

The above approach of integrating analytically (under certain assumptions) across the porous wall the species balances to obtain local soot consumption rates can be extended for the case of more reactions occurring in the porous wall. In the presence of a precious metal catalyst, the hydrocarbons and the carbon monoxide of the exhaust gases are also oxidized. It can be assumed that all the reactions in the porous wall occur hierarchically (according to their... 

In combustion systems it is generally desirable to minimize the concentration of intermediates, since it is important to obtain complete oxidation of the fuel. Figure 13.5 shows modeling predictions for oxidation of methane in a batch reactor maintained at constant temperature and pressure. After an induction time the rate of CH4 consumption increases as a radical pool develops. The formaldehyde intermediate builds up at reaction times below 100 ms, but then reaches a pseudo-steady state, where CH2O formed is rapidly oxidized further to CO. Carbon monoxide oxidation is slow as long as CH4 is still present in the reaction system once CH4 is depleted, CO (and the remaining CH2O) is rapidly oxidized to CO2. 

As the temperature rises, an endothermic reaction also occurs to an increasing extent in which carbon monoxide is formed from the carbon dioxide and carbon. Therefore, oxygen must be blown in with the chlorine to maintain the reaction temperature between 800 and 1200°C. The coke consumption per tonne of Ti02 is 250-300 kg. If C02-containing chlorine from the combustion of TiCl4 is used, the coke consumption increases to 350-450kg. 

The precipitation of mercuric acetylide resulted in alkali consumption so that titrating the excess hydroxide gave a direct measure of the amount of acetylide and hence the concentration of acetylene in the gas mixture. The more usual method, precipitating silver acetylide from ammoniacal silver nitrate, was unsatisfactory in this case since the carbon monoxide in the product gases reduced the silver nitrate to silver. 

Hydrogen, psia Carbon Monoxide, psia Rate of Hydrogen Consumption, lbs/min... 

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