Internal combustion carbon monoxide

PGM catalyst technology can also be appHed to the control of emissions from stationary internal combustion engines and gas turbines. Catalysts have been designed to treat carbon monoxide, unbumed hydrocarbons, and nitrogen oxides in the exhaust, which arise as a result of incomplete combustion. To reduce or prevent the formation of NO in the first place, catalytic combustion technology based on platinum or palladium has been developed, which is particularly suitable for appHcation in gas turbines. Environmental legislation enacted in many parts of the world has promoted, and is expected to continue to promote, the use of PGMs in these appHcations. 

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. 

Almost all the major car, bus, and truck manufacturers have developed compressed natural gas engines and vehicles. These manufacturers have been able to offer better performance (due to higher octane) and far lower emissions of nitrogen oxides, carbon monoxide, particulate matter, and carbon dioxide to the atmosphere. In 1998, Honda introduced the cleanest internal combustion engine vehicle ever commercially produced the natural gas Civic GX with emissions at one-tenth the state of California s Ultra Low Emission Vehicle standard. Primarily due to the high octane of natural gas, Honda achieved these results without sacrificing performance. 

The classes of major primary pollutants that are important in urban areas are listed in Table 2-1. The pollutants most responsible for oxidant formation in the air are the nitrogen oxides, hydrocarbons, aldehydes, and carbon monoxide. The internal-combustion engine is a major source of emission of these primary pollutants, although many stationary sources. 

Cherian, M. A., P. Rhodes, R. J. Simpson, and G. Dixon-Lewis. 1981. Kinetic modelling of the oxidation of carbon monoxide in flames. 18th Symposium (International) on Combustion Proceedings. Pittsburgh, PA The Combustion Institute. 385-96. 

All these cells are anodically combusting hydrogen, although MCFCs and SOFCs may be supplied with methane or carbon monoxide from which by internal reforming and/or shift reaction with steam within the cell the hydrogen may be generated in situ (98-100). 

Carbon monoxide Carbon monoxide is an odorless, colorless, and toxic gas. Sources of carbon monoxide volcanic activity, internal combustion engines, unvented kerosene and gas space heaters, generators and other gasoline-powered equipment, tobacco smoke. 

Environmental Protection Agency without any modifications or accessories.32 However, concerns over cancer from Diesel exhaust have made the issue quite complicated in recent years, but those concerns are only for long-term effects. In any event, Diesels have always produced far less than 1%/vol. carbon monoxide, which is still the CO standard for all internal combustion engines. Gasoline engines have only met the same standard after many years of intensive research and the addition of many engine modifications and complex accessories including catalytic converters. 

Carbon monoxide emissions from internal combustion engines are commonly plotted as functions of air/fuel ratio or fuel/air ratio. Fuel/air ratio is merely the reciprocal of air/fuel ratio.34 It has generally been accepted by the automotive experts that the CO level of Diesel exhaust is related chiefly to these ratios and not to other factors, such as rpm. 

Graph 3 Comparison of carbon monoxide emissions from Diesel and internal combustion engines.33 ... 

To permit controlled carbon monoxide combustion without combustion promotor, the carbon monoxide and oxygen must be held in intimate contact with the catalyst at a temperature, residence time and bed density to allow adequate carbon monoxide burning to proceed, while the heat evolved is absorbed by the catalyst, and to protect regenerator internals and downstream equipment from the excessive temperature associated with afterburning. 

Carbon monoxide CO Colourless, odourless and extremely toxic gas, produced by incomplete combustion of carbon-containing compounds (e.g. in internal combustion engines-exhaust fumes). 

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